problem solving riddles

70+ Challenging Riddles for Adults (With Answers)

Test your logical thinking and problem-solving skills with these fun brain teasers and puzzles. These riddles for adults start on a light note with a dirty joke or fun riddle, and then gradually dives into the trickier puzzles. Towards the end, you’ll find the harder riddles, the ones that are more complicated and more difficult to solve… 

Funny Riddles 

Here are some easy riddles , ones that are funny and that you most likely have heard before. Keep in mind that there will be some dirty riddles in here that might not be appropriate for a kid. But if you’re an adult–enjoy! 

I am a rock group with four members. All dead, one was assassinated. What am I?

Mt. Rushmore.

What time is it when an elephant sits on a fence?

It’s time to fix the fence.

What’s messy and can be really annoying and/or tricky to clean up after sex?

I saw a boat full of people, yet there wasn’t a single person on the boat. How is that possible?

They were all married.

Why is Europe like a frying pan?

Because it has Greece at the bottom. 

I go in hard, come out soft, and you love to blow me. What am I?

Chewing gum.

What has ten letters and starts with gas?

Automobile. 

I start with a “p” and ends with “o-r-n,” and I’m a major player in the film industry. What am I?

What goes up but never comes down?

A king, a queen, and two twins all lay in a large room. How are there no adults in the room?

They’re all beds!

Some people prefer being on top, others prefer being on the bottom, and it always involves a bed. What am I? 

A bunk bed.

Why can’t we take a picture of a man with a wooden leg ?

The wooden leg is not a camera.

I assist with erections. Sometimes, giant balls hang from me. I’m known as a big swinger. What am I?

Samuel was out for a walk when it started to rain. He did not have an umbrella and he wasn’t wearing a hat. His clothes were soaked, yet not a single hair on his head got wet. How could this happen?

Because Samuel is bald! 

All-day long it’s in and out. I discharge loads from my shaft. Both men and women go down on me. What am I?

An elevator.

What has four legs like a dog, two eyes like a dog, looks just like a dog but is not a dog?

A picture of a dog! 

What tastes better than it smells?

Your tongue! 

What is as light as a feather, but even the strongest man in the world can’t hold it in for long?

His breath. 

What does a teddy bear do when it rains? 

It gets wet! 

What’s long and hard and has cum in it?

A cucumber.

Challenging Riddles 

Here are some brain teasers that might require some problem-solving skills and logical thinking . They’re tricky, but not impossible to answer . It’s just some good riddles that will get you to really use your brain .  

You walk into a room that contains a match, a kerosene lamp, a candle, and a fireplace. What would you light first?

The match. 

How many letters are in the alphabet?

There are 11 letters in “the alphabet”.

A murderer is condemned to death. He has to choose between three rooms: the first is full of raging fires; the second, assassins with loaded guns, and the third, with lions who haven’t eaten in years. Which room is the safest?

The room with the lions because the lions are already dead. 

What five- letter word stays the same when you take away the first, third, and last letter ?

All 5 sisters are busy. Ann is reading a book, Rose is cooking, Katy is playing chess, and Mary is doing the laundry. What is the 5th sister doing?

She’s playing chess, of course! 

A man is asked what his daughters look like. He answers, “they are all blondes, but two, all brunettes, but two, and all redheads, but two.” How many daughters does he have?

Three. One is blonde, one is brunette, and one is a redhead.

David’s father has three sons: Snap, Crackle and…? 

You always find me in the past, I can be created in the present, but the future can never taint me. What am I?

A man is found hanging dead from the ceiling of a room. The room’s dimensions are 15 x 15 x 15. The man is only 6ft tall and the rope was only 2ft long. There are no windows and only one door into the room. The door is bolted shut from the inside and there is a puddle of water under the man . How did he kill himself?

The man stood on a block of ice.

How can you drop a raw egg on the concrete floor without cracking it?

The egg won’t crack the concrete floor! 

What has thirteen hearts but no other organs?

A deck of cards.

In a bus, there is a 26-year-old pregnant lady, a 30-year-old policeman, a 52-year-old random woman, and the driver who is 65 years old. Who is the youngest?

The baby of the pregnant lady.

Two in a corner, 1 in a room, 0 in a house, but 1 in a shelter. What am I?

The letter “R”

What English word does the following: the first two letters signify a male, the first three letters signify a female, the first four letters signify a great person , while the entire word signifies a great woman. What is the word ?

A boy and an engineer were fishing. The boy is the son of the engineer but the engineer is the father of the boy. Then who is the engineer?

The engineer is the boy’s mother. 

In a one-story pink house, there was a pink person , a pink cat, a pink fish, a pink computer, a pink chair, a pink table, a pink telephone, a pink shower– everything was pink! What color were the stairs?

There weren’t any stairs, it was a one-story house!

A plane crashed between the border of Canada and America. Where do you bury the survivors?

They are survivors, you don’t bury them.

A woman is sitting in her hotel room when there is a knock at the door. She opened the door to see a man whom she had never seen before. He said, “Oh I’m sorry. I have made a mistake. I thought this was my room.” He then went down the corridor and in the elevator. The woman went back into her room and phoned security. What made the woman so suspicious of this man?

You don’t knock on your own hotel room door! 

What is special about the number 854,917,632?

It’s the numbers from 1-9 in alphabetical order.

What word in the English language has three consecutive double letters ?

Bookkeeper.

My first is in chocolate but not in ham, my second’s in cake and also in jam, my third at tea-time is easily found, my whole is a friend who’s often around. What am I?

Two fathers and two sons are in a car, yet there are only three people in the car. How?

They are a grandfather, father, and son.

A woman shoots her husband, then holds him underwater for five minutes. Next, she hangs him. Right after, they enjoy a lovely dinner. Explain.

She took a picture of him and developed it in her darkroom.

A man is trapped in a room. The room has only two possible exits: two doors. Through the first door, there is a room constructed from magnifying glasses. The blazing hot sun instantly fries anything or anyone that enters. Through the second door, there is a fire-breathing dragon. How does the man escape?

He waits until night time and then goes through the first door.

Poor people have it. Rich people need it. If you eat it you die. What is it?

A is the brother of B. B is the brother of C. C is the father of D. So how is D related to A?

A is D’s aunt.

A man was found murdered on Sunday morning. His wife immediately called the police. The police went to the crime scene and question the wife and staff and got these alibis: The wife said she was sleeping, the cook was eating breakfast, the gardener was picking vegetables, the maid was getting the mail, the butler was cleaning the closet. The police instantly arrested the murderer. Who did it and how did they know?

It was the Maid. She said she was getting the mail but there’s no mail on Sundays.

Difficult Riddles

All of the puzzles below are considered to be logic riddles , ones that you’ll really need to think about to get the answer . 

Tim and Mel are long-distance lovers. Tim has just purchased an engagement ring for Mel and wants to mail it to her. Unfortunately, the only way to ensure the ring will be received is to place a lock on the package. Tim has locks and Mel has locks but neither have keys for each others’ locks. How can they ensure the ring isn’t stolen?

Tim places a lock on the package and sends it to Mel. Mel places one of her locks on the package and sends it back to Tim. Tim removes his lock and sends the package back to Mel.

I am a word of 5 letters and people eat me. If you remove the first letter, I become a form of energy. Remove the first two and I’m needed to live. Scramble the last 3 and you can drink me. What am I?

Wheat, heat, eat, tea

Which English word is the odd one out – Stun, Ton, Evil, Letter , Mood, Bad, Snap, Straw?

The person who makes it has no need of it; the person who buys it has no use for it. The person who uses it can neither see nor feel it. What is it?

The answer I give is yes, but what I mean is no. What was the question?

“Do you mind ?”

My buddies and I were inseparable mates Til one by one were we split My teacher, she gave me a smack on the pate And off in the corner I sit. Admittedly still I’m not hitting the books Though now I’m hugging a tree I guess in the end it’s not bad as it looks I went from a C to a B…

(Clue: it’s an object)

What can go up a chimney down, but can’t go down a chimney up?

An umbrella.

What can you hold in your right hand, but never in your left hand?

Your left hand.

A man is found murdered in his office. The suspects are Peter, Julie, Jason, Molly, and Brian. In the office is a calendar with the numbers 6,4,9,10,11 written in blood. Who is the killer?

Jason is the killer. The numbers indicate months and the first letter of each month spells the name of the murderer, e.g. the 6th month is June and the first letter of June is J, the 4th month is April and the first letter of April is a, and so on.

There are 3 switches outside of a room, all in the ‘off’ setting. One of them controls a lightbulb inside the room, the other two do nothing. You cannot see into the room, and once you open the door to the room, you cannot flip any of the switches anymore. Before going into the room, how would you flip the switches in order to be able to tell which switch controls the light bulb?

Flip the first switch and keep it flipped for five minutes. Then unflip it, and flip the second switch. Go into the room. If the lightbulb is off but warm, the first switch controls it. If the light is on, the second switch controls it. If the light is off and cool, the third switch controls it.

You walk into a creepy house by yourself. There is no electricity, plumbing or ventilation. Inside you notice 3 doors with numbers on them. Once you open the doors you will die a particular way. Door #1 You’ll be eaten by a lion who is hungry. Door #2 You’ll be stabbed to death. Door #3 There is an electric chair waiting for you. Which door do you pick?

Door #3, Since There Is No Electricity To Harm You.

With pointed fangs I sit and wait, with piercing force I serve out fate. Grabbing bloodless victims, proclaiming my might; physically joining with a single bite. What am I?

Short Riddles: Math Edition 

Everyone loves a good ol math riddle!   Math riddles are a great way to test your smarts and make sure that you actually did learn something in school: 

I have two coins equaling fifteen cents. One of them is not a nickel. What are the two coins?

A dime and a nickel. One of the coins is not a nickel, but the other one is. 

Mom and dad have four daughters, and each daughter has one brother . How many people are in the family?

If 9999=4, 8888=8, 1816=6, 1212=0, then 1919=? (Clue: Closed areas.)

2. 9999 has 4 closed areas (the top of the ‘9’).8888 has 8 closed areas (the top and bottom parts of 8 and there are no other digits). 1816 has 3 closed areas (top and bottom of 8 and bottom of 6, and it has 2 other digits (3 * 2 = 6)). 1212 has 0 closed areas, (0 * 4 = 0).

If you multiply me by any other number, the answer will always remain the same. What number am I?

Which is correct: 18 plus 19 is 36. Or 18 plus 19 are 36?

Actually, both are incorrect – 18 plus 19 is 37!

When does 11+3=2?

On a clock.

There was a large truck that needed to cross a 20-mile long bridge. Unfortunately, the bridge could only hold the weight of 12000 lbs. Even a single pound extra, the bridge would collapse. However, the weight of the truck is exactly 12000 lbs. The driver carefully drove and crossed almost 85% distance of the bridge. He stopped to get a small break. Suddenly, a bird landed on the truck. Did the bridge collapse? 

No, the bridge doesn’t collapse. The truck almost crossed 85% of total distance. Equivalent diesel would have been lost. So the extra weight of the bridge doesn’t add any extra load to the bridge.

3 hens lay 3 eggs in 3 days. How many eggs do 12 hens give in 12 days?

48 eggs. One hen lays 1 egg in 3 days or 4 eggs in 12 days. 12 hens give 48 eggs in 12 days.

Challenging Adult Riddles 

Here are some fun yet complicated riddles for adults wanting to challenge themselves and really use the depths of their brains to figure out the answer (s).

Hard Mythology Riddle  

There is a mythological story of a Sphinx, a monster with the body of a lion and the head of a woman. Apparently, the Sphinx sat on top of a rock along the road to the city of Thebes, stopping travelers and proposing to them a riddle . The Sphinx claimed that whoever failed the riddle would be killed, and evidently, not pass through to the city. This is the riddle : 

What animal walks on four legs in the morning, two legs during the day, and three legs in the evening?

Oedipus, the king of Thebes, figured out the answer to this logic puzzle :

Man, who in childhood creeps on hands and knees, in manhood walks erect, and in old age with the aid of a staff. (Morning, day, and night are representative of the stages of life.)

Buried Treasure Riddle

The best way to find the right answer to this brainteaser is through logic and deductive reasoning. 

After a storm tears through the Hex Archipelago, you find five grizzled survivors in the water. Shivering their timbers, they explain that they’re the former crew of the great pirate Greenbeard, who marooned them after they tried to mutiny. Each was bound up in a different spot on a small island, until the storm washed them out to sea. In gratitude for saving them, they reveal a secret: the island they were on is also where Greenbeard has buried his treasure hoard. But when the sailors try to describe the island, something seems off. All agree it was flat and barren with no prominent features except for some trees. Yet each pirate claims they saw a different number of trees, ranging from two to six. The pirate who saw two trees says the treasure was buried right at his feet. When you fly your hot air balloon over the area to investigate, you see hundreds of small islands, each with exactly six trees. The next storm will be here soon, so you’ll have to hurry and narrow your search. What does the island with Greenbeard’s treasure look like from the sky? And where will the treasure be on that island? 

• All islands have exactly 6 trees of equal height. 
• The islands are all flat, have no obstructions other than trees and their precise shapes aren’t important.
• Each pirate was confined in a specific spot and saw a different number of trees, ranging from 2 to 6. They could look all around but not move. 
• The treasure was buried at the feet of the pirate who saw 2 trees.

No, the pirates aren’t delirious from dehydration. Remember, each was confined to a separate point on the island, and no two of them could see the same number of trees. That means that for all but one pirate, something was blocking their view. And since there are no other features on the island, that something could only have been other trees.

A pirate would see fewer trees when two or more fell along a straight line from their vantage point. So we need to find the island where five different pirates standing in different spots would each see a different number of trees. Virtually every island has a position from which you can see six trees. And on most islands there’s a position where 5 trees can be seen by standing in line with two of them. It turns out that the hardest locations to find are those with fewer visible trees precisely because they require more trees to line up with the viewer’s position. So how can we see just two trees. One way would be if all the trees were lined up in single file, such as on this island. Then, you could stand at the end of the line and see one, stand in the middle and see two, or stand anywhere else and see all six. But there’s no place from which you can see only three, four, or five, so one straight line of trees is out. So what about two lines of trees? So long as the lines aren’t parallel and they intersect over land, there’ll always be a position where the two lines converge from which you could see exactly two trees. And if they’re grouped two and four, or three and three, there are many arrangements in which you could also see three, four, five, and six trees. 

Fortunately for us, there’s only one island in the archipelago with two non-parallel lines of trees, and it’ll be buried at the intersection of the two lines. (X marks the spot!) You land on this island and dig up a chest containing a massive pile of tree seeds. 

Prisoner Hat Riddle

Here’s a great mind -boggling riddle :

100 prisoners are lined up single file. A blue or red hat is placed on each of their heads randomly. The prisoners cannot see the color of the hat on their own head, but they can see the colors of all the hats in front of them. The prisoner in the back can clearly see all 99 hats in front of him. The 50th prisoner in line can see the 49 hats in front of him, and the prisoner in the front of the line cannot see anything but the forest before him. Also, the prisoners don’t know the proportion of red hats to blue hats in advance—it could be 50/50, but it could also be any combination that adds to 100.

A guard is going to walk down the line, starting in the back, and ask each prisoner what color hat they have on. They can only answer “blue” or “red.” If they answer incorrectly or say anything else, they will be shot dead on the spot. If they answer correctly, they will be set free. Each prisoner can hear all of the other prisoners’ responses, as well as any gunshots that indicate an incorrect response. They can remember all of this information.

Before the executions begin, the prisoners get to huddle up and make a plan. How can the prisoners ensure that most people possible survive?

The prisoners come up with the following plan: 

If the first prisoner to speak—the one in the back of the line—sees an even number of blue hats, he will yell out “blue.” If he sees an odd number of blue hats, he will yell out “red.”

Let’s assume the first prisoner to speak yells out “blue,” indicating that he sees an even number of blue hats. Then the next prisoner to speak can look at the line in front of him, and if he sees an odd number of blue hats, he knows his hat must be blue to make the number even. Similarly, if he sees an even number of blue hats, he knows his hat must be red to keep it that way. The same logic works if the first prisoner yells out “red,” indicating that there are an odd number of blue hats.

The next prisoner in line listens to the prisoner behind him and takes that information into consideration. If he sees an even number of blue hats and the prisoner behind him yells “blue,” making the total number of blue hats odd, then he knows his hat must be blue to make the total number even again (of the 99 seen by the first prisoner). In the same situation, if his hat were red, the total number of blue hats would be odd (of the 99 seen by the first prisoner).

As you go down the line, each prisoner must count how many blue hats are behind them. Then he must consider the blue hats in front of him. If the number of blue hats behind a prisoner plus the blue hats he can see in front of him equals an odd number, then he knows his hat must be blue to make the total number even, or red to make the total number odd (not counting the very first prisoner).

The very first prisoner is the maybe-martyr of the group. He is imparting information to the rest of the group that has nothing to do with the hat on his own head, which he cannot know, and so his chances of living are only 50%.

More Riddles

• Riddles with Answers
• Short Riddles
• Riddles for Adults
• Riddles for Teens
• Riddles for Kids
• Funny Riddles
• Tricky Riddles
• Hard Riddles
• Easy Riddles
• Math Riddles

About the author

January Nelson

January Nelson is a writer, editor, and dreamer. She writes about astrology, games, love, relationships, and entertainment. January graduated with an English and Literature degree from Columbia University.

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These brain-teasers range from super-easy to downright mind-boggling.

Math Riddles

Funny riddles, hard riddles.

Ranging from super-tough head-scratchers to unbelievably easy queries, these riddles are just as fun for adults to solve as they are for kids . We've got everything from funny riddles for when you need a quick laugh to math riddles that will keep your mind sharp and help you learn a little along the way.

So get ready to put your logic and problem solving skills to the test and try your hand at the riddles below. Be sure to let us know which was your favorite in the comments!

Easy Riddles

Q: I'm not a blanket, yet I cover the ground; a crystal from heaven that doesn't make a sound. What am I?

A: Snowflake.

Q: I'm sweet and cold with a stick to hold; a treat on a hot day, worth more than gold. What am I?

A: Popsicle.

Q: What has a head but no brain?

A: A lettuce.

Q: Why do cats make good warriors?

A: Because they’ve got nine lives.

Q: I have a neck, but no head. I have two arms, but no hands. What am I?

A: A shirt.

Q: What word contains 26 letters but only has three syllables?

A: The alphabet.

Q: What comes down but never goes up?

Q: What five-letter word typed in all capital letters can be read the same upside down?

Q: The more you take, the more you leave behind. What am I?

A: Footsteps.

Q: David's father has three sons: Snap, Crackle and _____?

Q: What is more useful when it is broken?

Q: I am easy to lift, but hard to throw. What am I?

A: A feather.

Q: Where do you take a sick boat?

A: To the dock -tor.

Q: Which fish costs the most?

A: A goldfish.

Q: What goes up, but never comes down?

Q: A cowboy rode into town on Friday. He stayed for three nights and rode out on Friday. How is this possible?

A: His horse's name is Friday.

Q: What has a neck but no head?

A: A bottle.

Q: What is full of holes but still holds water?

A: A sponge.

Q: How do you spell COW in thirteen letters?

A: SEE O DOUBLE YOU.

Q: Why is Europe like a frying pan?

A: Because it has Greece at the bottom.

Q: What do the numbers 11, 69 and 88 all have in common?

A: They all read the same way when placed upside down.

Q: If 2 is company and 3 is a crowd, what are 4 and 5?

Q: I add 5 to 9 and get 2. The answer is correct, so what am I?

A: A clock. When it is 9 a.m., adding 5 hours would make it 2 p.m.

Q: Rachel goes to the supermarket and buys 10 tomatoes. Unfortunately, on the way back home, all but 9 get ruined. How many tomatoes are left in a good condition?

Q: What is 3/7 chicken, 2/3 cat, and 2/4 goat?

A: Chicago!

Q: If a zookeeper had 100 pairs of animals in her zoo, and two pairs of babies are born for each one of the original animals, then (sadly) 23 animals don’t survive, how many animals do you have left in total?

A: 977 animals (100 x 2 = 200; 200 + 800 = 1000; 1000 – 23 = 977)

Q: I saw my math teacher with a piece of graph paper yesterday.

A: I think he must be plotting something.

Q: If you multiply this number by any other number, the answer will always be the same. What number is this?

Q: I am an odd number. Take away a letter and I become even. What number am I?

Q: What three numbers give the same result when multiplied and added together?

A: 1, 2, and 3 (1 + 2 + 3 = 6 and 1 x 2 x 3 = 6).

Q: What's a single-digit number with no value?

Q: A tree doubled in height each year until it reached its maximum height over the course of ten years. How many years did it take for the tree to reach half its maximum height?

A: Nine years.

Q: How can you drop a raw egg from a height onto a concrete floor without cracking it?

A: Concrete floors are very hard to crack.

Q: What do you call a bear with no teeth?

A: A gummy bear.

Q: What has many rings but no fingers?

A: A phone.

Q: What can you break without touching it?

A: A promise.

Q: I sometimes run, but I can’t walk. What am I?

Q: It has keys, but no locks. It has space, but no room. You can enter, but can’t go inside. What is it?

A: A keyboard.

Q: I have pointed fangs, and I sit and wait. I have piercing force, and I crunch with weight. I grab my victims, but they do not fight. I join them each with a single, quick bite. What am I?

A: A stapler.

Q: Pronounced as one letter, And written with three, two letters there are, and two only in me. I’m double, I’m single, I’m black blue and gray, I’m read from both ends, and the same either way. What am I?

Q: Who has married many women but was never married?

A: The priest.

Q: Forward, I am heavy; backward, I am not. What am I?

Q: What can you hold in your right hand, but never in your left hand?

A: Your left hand.

Q: If two snakes marry, what will their towels say?

A: Hiss and hers.

Q: What does a man do only once in his lifetime, but women do once a year after they are 29?

A: Turn 30.

Q: Ask this question all day long, but always get completely different answers, and yet all the answers will be correct. What is the question?

A: What time is it?

Q: What loses its head in the morning but gets it back at night?

A: A pillow.

Q: Four cars come to a four-way stop, each coming from a different direction. They can’t decide who got there first, so they all go forward at the same time. All four cars go, but none crash into each other. How is this possible?

A: They all made right-hand turns.

Q: I have a head like a cat and feet like a cat, but I am not a cat. What am I?

A: A kitten.

Q: Who makes it, has no need of it. Who buys it, has no use for it. Who uses it can neither see nor feel it. What is it?

A: A coffin.

Q: What has hands but cannot clap?

A: A clock.

Q: Paul's height is six feet, he's an assistant at a butcher's shop, and wears size 9 shoes. What does he weigh?

Q: What gets broken without being held?

Q: Poor people have it. Rich people need it. If you eat it you die. What is it?

A: Nothing.

Q: What is the longest word in the dictionary?

A: Smiles, because there is a mile between each ‘s’.

Q: Throw away the outside and cook the inside, then eat the outside and throw away the inside. What is it?

A: Corn on the cob.

Q: What is at the end of a rainbow?

A: The letter W!

Q: What kind of tree can you carry in your hand?

Q: They come out at night without being called, and are lost in the day without being stolen. What are they?

Q: What is always in front of you, but can’t be seen?

A: The future.

Q: You’ll find me in Mercury, Earth, Mars, Jupiter, Saturn and Uranus. But never Neptune, or Venus. What am I?

A: The letter “R”.

Q: How many months have 28 days?

A: Every month has 28 days.

Q: I can be cracked, made, told and played. What am I?

Q: I cannot talk, but I always reply when spoken to. What am I?

A: An echo.

Q: When is the top of a mountain similar to a savings account?

A: When it peaks one’s interest.

Q: A man goes out for a walk during a storm with nothing to protect him from the rain. He doesn’t have a hat, a hood or an umbrella. But by the end of his walk, there isn’t a single wet hair on his head. Why doesn’t the man have wet hair?

A: He’s bald.

Q: I love to dance and twist. I shake my tail as I sail away. When I fly wingless into the sky. What am I?

Q: When you stop to look, you can always see me. But if you try to touch me, you can never feel me. Although you walk towards me, I remain the same distance from you. What am I?

A: The horizon.

Q: You see a boat filled with people. It has not sunk. But when you look back, you don’t see a single person on the boat. Why?

A: All the people on board are married.

Q: What is it that no one wants to have, but no one wants to lose either?

A: A lawsuit.

Q: I welcome the day with a show of light, I stealthily came here in the night.I bathe the earthy stuff at dawn, But by noon, alas! I'm gone.

A: The morning dew.

Q: What goes through cities and fields, but never moves?

Q: What can be touched but can't be seen?

A: Someone’s heart.

Q: In a bus, there is a 26-year-old pregnant lady, a 30-year-old policeman, a 52-year-old random woman, and the driver who is 65 years old. Who is the youngest?

A: The baby of the pregnant lady.

Q: When it is alive we sing, when it is dead we clap our hands. What is it?

A: A birthday candle.

Q: What can go through glass without breaking it?

Q: What gets bigger the more you take away?

Q: I have no life, but I can die. What am I?

A: A battery.

Q: What kind of room has no walls, door or windows?

A: A mushroom.

Q: It belongs to you, but your friends use it more. What is it?

A: Your name.

Q: What two things can you never eat for breakfast?

A: Lunch and dinner.

Q: I make a loud sound when I’m changing. When I do change, I get bigger but weigh less. What am I?

A: Popcorn.

Q: I’m orange, I wear a green hat and I sound like a parrot. What am I?

A: A carrot.

Q: What runs all around a backyard, yet never moves?

A: A fence.

Q: Take off my skin — I won't cry, but you will! What am I?

A: An onion.

Q: What invention lets you look right through a wall?

A: A window.

Q: What is always on its way but never arrives?

A: Tomorrow.

Q: Two girls were born to the same mother, on the same day, at the same time, in the same month and year, and yet they're not twins. How can this be?

A: The two babies are two of a set of triplets.

Q: What has a bottom at the top?

A: Your legs.

Q: What can you catch but never throw?

Q: What has many teeth but cannot bite?

Q: What has branches, but no fruit, trunk or leaves?

Q: What thrives when you feed it but dies when you water it?

Q: What do you buy to eat but never consume?

A: Cutlery.

Q: Two fathers and two sons are in a car, yet there are only three people in the car. How?

A: They are grandfather, father, and son.

Q: A bus driver goes the wrong way down a one-way street. He passes the cops, but they don’t stop him. Why?

A: He was walking.

Q: If an electric train is traveling south, then which way is the smoke going?

A: There is no smoke — it's an electric train.

Q: Where is the only place where today comes before yesterday?

A: The dictionary.

Q: What can you put in a bucket to make it weigh less?

Q: How can kids drink beer and not get drunk?

A: By sticking to root beer.

Q: What is black when it’s clean and white when it’s dirty?

A: A chalkboard.

Q: I have one eye but am unable to see. What am I?

A: A needle.

Q: What two keys can’t open any door?

A: A monkey and a donkey.

Q: A man and his boss have the same parents but are not siblings. How is this possible?

A: He’s self-employed.

Cameron (she/her) is a staff writer for Good Housekeeping , where she covers everything from holidays to food. She is a graduate of Syracuse University, where she received a B.A. in magazine journalism. In her spare-time she can be found scrolling TikTok for the latest cleaning hacks and restaurant openings, binge-watching seasons of Project Runway or online shopping.

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100+ BRAIN TEASERS FOR KIDS AND ADULTS (WITH ANSWERS)

Brain teasers that require thought, intellect, and a dab of creativity. Moreover, teasing your brain will require you to think hard and sometimes think outside the box.

• Brain Teasers

Brain Teasers to Solve

A brain teaser is a type of puzzle that requires thinking outside of the box and using logic, creativity, and problem-solving skills to solve. It is designed to challenge and stimulate the brain, often requiring a combination of math, language, and visual skills. Brain teasers can come in many different forms, such as riddles , puzzles, and games. They can range in difficulty from easy to extremely challenging and can be solved individually or as a group. The goal of a brain teaser is often to find a hidden solution or pattern that is not immediately obvious and to use critical thinking and reasoning to arrive at the answer. Solving brain teasers can improve cognitive function, memory, and creativity, and can also be a fun and entertaining way to pass the time.

In addition, parents introduce their children to riddles for many reasons.  Solving riddles for kids can significantly accelerate brain development.

You Live In A One Story House Made Entirely Of Redwood

Carnival Trick Riddle

The mustard family riddle.

Six Faces 21 Eyes

A woman shoots her husband riddle.

There Are 10 People In A Room

Always In You, Sometimes On You; If I Surround You I Can Kill You

Strange subtraction, i have a little house in which i live all alone. it has no doors, i am a word of six; my first three letters refer to an automobile, two girls have the same parents and were born at the same hour, a time when they are green a time when they're brown, when can you add two to eleven and get one, sometimes i am born in silence, other times no i am unseen, a pregnant lady named her children, the death of romeo and juliet, i'm not clothes but i cover your body, three playing cards in a row, building riddle, search riddles, follow riddles, share riddles.

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20 Tough Riddles for Adults That Will Have You Scratching Your Head

Put your logic and math skills to the test. No cheating!

Gear-obsessed editors choose every product we review. We may earn commission if you buy from a link. Why Trust Us?

So go grab a pencil and a piece of scratch paper and prepare to rip your hair out (and we really do mean that in the best way possible). When you think you’ve got the right answer, click the link at the bottom of each riddle to find the solution. Got it wrong? No worries, you have 19 other riddles to test out.

Navigate Through Our Riddles:

Puzzmo / The King’s Orders / How Many Eggs? / The Gold Chain / Pickleball / Circuit Breaker / Two Trains, Two Grandmas / Ant Math / Peppermint Patty / Great American Rail Trail / A Cruel SAT Problem / Movie Stars Cross a River / Tribute to a Math Genius / One Belt, One Earth / Elbow Tapping / Whiskey Problem / Doodle Problem / Stumping Scientists / What ’ s On Her Forehead? / Keanu for President / Who Opened the Lockers?

Riddle No. 1: The King’s Orders Make for One Hell of a Brain Teaser

Difficulty: easy.

King Nupe of the kingdom Catan dotes on his two daughters so much that he decides the kingdom would be better off with more girls than boys, and he makes the following decree: All child-bearing couples must continue to bear children until they have a daughter!

But to avoid overpopulation, he makes an additional decree: All child-bearing couples will stop having children once they have a daughter! His subjects immediately begin following his orders.

After many years, what’s the expected ratio of girls to boys in Catan?

The likelihood of each baby born being a girl is, of course, 50 percent.

Ready for the solution? Click here to see if you’re right .

Riddle No. 2: How Many Eggs Does This Hen Lay?

This problem is in honor of my dad, Harold Feiveson. It’s due to him that I love math puzzles, and this is one of the first problems (of many) that he gave me when I was growing up.

A hen and a half lays an egg and a half in a day and a half. How many eggs does one hen lay in one day?

Riddle No. 3: The Gold Chain Math Problem Is Deceptively Simple

Difficulty: moderate.

You’re rummaging around your great grandmother’s attic when you find five short chains each made of four gold links. It occurs to you that if you combined them all into one big loop of 20 links, you’d have an incredible necklace. So you bring it into a jeweler, who tells you the cost of making the necklace will be $10 for each gold link that she has to break and then reseal.

How much will it cost?

Riddle No. 4: Try to Solve This Pickleball Puzzle

Difficulty: 🚨hard🚨.

Kenny, Abby, and Ned got together for a round-robin pickleball tournament, where, as usual, the winner stays on after each game to play the person who sat out that game. At the end of their pickleball afternoon, Abby is exhausted, having played the last seven straight games. Kenny, who is less winded, tallies up the games played:

Kenny played eight games

Abby played 12 games

Ned played 14 games

Who won the fourth game against whom?

How many total games were played?

Riddle No. 5: Our Circuit Breaker Riddle Is Pure Evil. Sorry.

The circuit breaker box in your new house is in an inconvenient corner of your basement. To your chagrin, you discover none of the 100 circuit breakers is labeled, and you face the daunting prospect of matching each circuit breaker to its respective light. (Suppose each circuit breaker maps to only one light.)

To start with, you switch all 100 lights in the house to “on,” and then you head down to your basement to begin the onerous mapping process. On every trip to your basement, you can switch any number of circuit breakers on or off. You can then roam the hallways of your house to discover which lights are on and which are off.

What is the minimum number of trips you need to make to the basement to map every circuit breaker to every light?

The solution does not involve either switching on or off the light switches in your house or feeling how hot the lightbulbs are. You might want to try solving for the case of 10 unlabeled circuit breakers first.

Riddle No. 6: Two Trains. Two Grandmas. Can You Solve This Tricky Math Riddle?

Jesse’s two grandmothers want to see him every weekend, but they live on opposite sides of town. As a compromise, he tells them that every Sunday, he’ll head to the subway station nearest to his apartment at a random time of the day and will hop on the next train that arrives.

If it happens to be the train traveling north, he’ll visit his Grandma Erica uptown, and if it happens to be the train traveling south, he’ll visit his Grandma Cara downtown. Both of his grandmothers are okay with this plan, since they know both the northbound and southbound trains run every 20 minutes.

But after a few months of doing this, Grandma Cara complains that she sees him only one out of five Sundays. Jesse promises he’s indeed heading to the station at a random time each day. How can this be?

The trains always arrive at their scheduled times.

Riddle No. 7: Here’s a Really F@*#ing Hard Math Problem About Ants

Max and Rose are ant siblings. They love to race each other, but always tie, since they actually crawl at the exact same speed. So they decide to create a race where one of them (hopefully) will win.

For this race, each of them will start at the bottom corner of a cuboid, and then crawl as fast as they can to reach a crumb at the opposite corner. The measurements of their cuboids are as pictured:

If they both take the shortest possible route to reach their crumb, who will reach their crumb first? (Don’t forget they’re ants, so of course they can climb anywhere on the edges or surface of the cuboid.)

Remember: Think outside the box.

Riddle No. 8: This Peppermint Patty Riddle Is Practically Impossible

You’re facing your friend, Caryn, in a “candy-off,” which works as follows: There’s a pile of 100 caramels and one peppermint patty. You and Caryn will go back and forth taking at least one and no more than five caramels from the candy pile in each turn. The person who removes the last caramel will also get the peppermint patty. And you love peppermint patties.

Suppose Caryn lets you decide who goes first. Who should you choose in order to make sure you win the peppermint patty?

First, solve for a pile of 10 caramels.

Riddle No. 9: Can You Solve the Great American Rail-Trail Riddle?

This problem was suggested by the physicist P. Jeffrey Ungar.

Finally, the Great American Rail-Trail across the whole country is complete! Go ahead, pat yourself on the back—you’ve just installed the longest handrail in the history of the world, with 4,000 miles from beginning to end. But just after the opening ceremony, your assistant reminds you that the metal you used for the handrail expands slightly in summer, so that its length will increase by one inch in total.

“Ha!” you say, “One inch in a 4,000 mile handrail? That’s nothing!” But … are you right?

Let’s suppose when the handrail expands, it buckles upward at its weakest point, which is in the center. How much higher will pedestrians in the middle of the country have to reach in summer to grab the handrail? That is, in the figure below, what is h ? (For the purposes of this question, ignore the curvature of the Earth and assume the trail is a straight line.)

Pythagoras is a fascinating historical figure.

Riddle No. 10: This Riddle Is Like an Especially Cruel SAT Problem. Can You Find the Answer?

Amanda lives with her teenage son, Matt, in the countryside—a car ride away from Matt’s school. Every afternoon, Amanda leaves the house at the same time, drives to the school at a constant speed, picks Matt up exactly when his chess club ends at 5 p.m., and then they immediately return home together at the same constant speed. But one day, Matt isn’t feeling well, so he leaves chess practice early and starts to head home on his portable scooter.

After Matt has been scooting for an hour, Amanda comes across him in her car (on her usual route to pick him up), and they return together, arriving home 40 minutes earlier than they usually do. How much chess practice did Matt miss?

Consider the case where Amanda meets Matt exactly as she’s leaving their house.

Riddle No. 11: Can You Get These 3 Movie Stars Across the River?

Three movie stars, Chloe, Lexa, and Jon, are filming a movie in the Amazon. They’re very famous and very high-maintenance, so their agents are always with them. One day, after filming a scene deep in the rainforest, the three actors and their agents decide to head back to home base by foot. Suddenly, they come to a large river.

On the riverbank, they find a small rowboat, but it’s only big enough to hold two of them at one time. The catch? None of the agents are comfortable leaving their movie star with any other agents if they’re not there as well. They don’t trust that the other agents won’t try to poach their star.

For example, Chloe’s agent is okay if Chloe and Lexa are alone in the boat or on one of the riverbanks, but definitely not okay if Lexa’s agent is also with them. So how can they all get across the river?

There isn’t just one way to solve this problem.

Riddle No. 12: This Ludicrously Hard Riddle Is Our Tribute to a Late Math Genius. Can You Figure It Out?

On April 11, John Horton Conway , a brilliant mathematician who had an intense and playful love of puzzles and games, died of complications from COVID-19. Conway is the inventor of one of my favorite legendary problems (not for the faint of heart) and, famously, the Game of Life . I created this problem in his honor.

Carol was creating a family tree, but had trouble tracking down her mother’s birthdate. The only clue she found was a letter written from her grandfather to her grandmother on the day her mother was born. Unfortunately, some of the characters were smudged out, represented here with a “___” . (The length of the line does not reflect the number of smudged characters.)

“Dear Virginia,

Little did I know when I headed to work this Monday morning, that by evening we would have a beautiful baby girl. And on our wedding anniversary, no less! It makes me think back to that incredible weekend day, J___ 27th, 19___ , when we first shared our vow to create a family together, and, well, here we are! Happy eighth anniversary, my love.

Love, Edwin”

The question: When was Carol’s mother born?

This problem is inspired by Conway’s Doomsday Rule .

Riddle No. 13: To Solve This Twisty Math Riddle, You Just Need One Belt and One Earth

Imagine you have a very long belt. Well, extremely long, really … in fact, it’s just long enough that it can wrap snugly around the circumference of our entire planet. (For the sake of simplicity, let’s suppose Earth is perfectly round, with no mountains, oceans, or other barriers in the way of the belt.)

Naturally, you’re very proud of your belt. But then your brother, Peter, shows up—and to your disgruntlement, he produces a belt that’s just a bit longer than yours. He brags his belt is longer by exactly his height: 6 feet.

If Peter were also to wrap his belt around the circumference of Earth, how far above the surface could he suspend the belt if he pulled it tautly and uniformly?

Earth’s circumference is about 25,000 miles, or 130 million feet … but you don’t need to know that to solve this problem.

Riddle No. 14: This Elbow Tapping Riddle Is Diabolical. Good Luck Solving It.

In some future time, when the shelter-in-place bans are lifted, a married couple, Florian and Julia, head over to a bar to celebrate their newfound freedom.

They find four other couples there who had the same idea.

Eager for social contact, every person in the five couples enthusiastically taps elbows (the new handshake) with each person they haven’t yet met .

It actually turns out many of the people had known each other prior, so when Julia asks everyone how many elbows they each tapped, she remarkably gets nine different answers!

The question: How many elbows did Florian tap?

What nine answers did Julia hear?

Riddle No. 15: You’ll Need a Drink After Trying to Solve This Whisky Riddle

Alan and Claire live by the old Scottish saying, “Never have whisky without water, nor water without whisky!” So one day, when Alan has in front of him a glass of whisky, and Claire has in front of her a same-sized glass of water, Alan takes a spoonful of his whisky and puts it in Claire’s water. Claire stirs her whisky-tinted water, and then puts a spoonful of this mixture back into Alan’s whisky to make sure they have exactly the same amount to drink.

So: Is there more water in Alan’s whisky, or more whisky in Claire’s water? And does it matter how well Claire stirred?

The size of the spoon does not matter.

Riddle No. 16: The Doodle Problem Is a Lot Harder Than It Looks. Can You Solve It?

This week’s riddle is relatively simple—but sinister all the same.

The question: Can you make 100 by interspersing any number of pluses and minuses within the string of digits 9 8 7 6 5 4 3 2 1? You can’t change the order of the digits! So what’s the least number of pluses and minuses needed to make 100?

For instance, 98 - 7 - 6 + 54 - 32 shows one way of interspersing pluses and minuses, but since it equals 107, it’s not a solution.

I call this a “doodle problem”: one that’s best worked on during meetings where you might be doodling otherwise.

You might want to start looking for solutions that use a total of seven pluses and minuses (although there are ways to use fewer).

Ready for the solution? Click here to see if you’re right.

Riddle No. 17: This Math Puzzle Stumped Every Scientist but One. Think You Can Crack It?

Difficulty: hard.

In honor of Freeman Dyson, the renowned physicist who died last month , here’s a legendary tale demonstrating his quick wit and incredible brain power.

One day, in a gathering of top scientists, one of them wondered out loud whether there exists an integer that you could exactly double by moving its last digit to its front. For instance, 265 would satisfy this if 526 were its exact double—which it isn’t.

After apparently just five seconds , Dyson responded, “Of course there is, but the smallest such number has 18 digits.”

This left some of the smartest scientists in the world puzzling over how he could have figured this out so quickly.

So given Dyson’s hint, what is the smallest such number?

My second grader has recently learned how to add a 3-digit number to itself using the classic vertical method:

18-digit numbers, of course, can be added in the same way.

Riddle No. 18: Figure Out What’s on Her Forehead

Cecilia loves testing the logic of her very logical friends Jaya, Julian, and Levi, so she announces:

“I’ll write a positive number on each of your foreheads. None of the numbers are the same, and two of the numbers add up to the third.”

She scribbles the numbers on their heads, then turns to Jaya and asks her what her number is. Jaya sees Julian has 20 on his forehead, and Levi has 30 on his. She thinks for a moment and then says, “I don’t know what my number is.” Julian pipes in, “I also don’t know my number,” and then Levi exclaims, “Me neither!” Cecilia gleefully says, “I’ve finally stumped you guys!”

“Not so fast!” Jaya says. “Now I know my number!”

What is Jaya’s number?

Jaya could be one of two numbers, but only one of those numbers would lead to Julian and Levi both not knowing their numbers. Why?

Riddle No. 19: Can You Get Keanu Reeves Elected As President?

It’s 2024, and there are five candidates running in the democratic primary: Taylor Swift, Oprah Winfrey, Mark Cuban, Keanu Reeves, and Dwayne Johnson. (Hey, it could happen.) As usual, the first primary is in Iowa.

In an effort to overcome its embarrassment after the 2020 caucus debacle , the Iowa Democratic Party has just announced a new, foolproof way of finding the best candidate: there will be four consecutive elections.

First, candidate 1 will run against candidate 2. Next, the winner of that will run against candidate 3, then that winner will run against candidate 4, and finally the winner of that election will run against the final candidate. By the transitive property, the winner of this last election must be the best candidate ... so says the Iowa Democratic Party.

Candidate Keanu has been feeling pretty low, as he knows he is ranked near the bottom by most voters, and at the top by none. In fact, he knows the Iowa population is divided into five equal groups, and that their preferences are as follows:

Keanu is childhood friends with Bill S. Preston, Esq., the new head of the Iowa Democratic Party. Preston, confident that the order of the candidates doesn’t matter for the outcome, tells Keanu he can choose the voting order of the candidates.

So what order should Keanu choose?

How would Keanu fare in one-to-one races against each candidate?

Riddle No. 20: Who Opened All These Damn Lockers?

There are 100 lockers that line the main hallway of Chelm High School. Every night, the school principal makes sure all the lockers are closed so that there will be an orderly start to the next day. One day, 100 mischievous students decide that they will play a prank.

The students all meet before school starts and line up. The first student then walks down the hallway, and opens every locker. The next student follows by closing every other locker (starting at the second locker). Student 3 then goes to every third locker (starting with the third) and opens it if it’s closed, and closes it if it’s open. Student 4 follows by opening every fourth locker if it’s closed and closing it if it’s open. This goes on and on until Student 100 finally goes to the hundredth locker. When the principal arrives later in the morning, which lockers does she find open?

Make sure you pay attention to all of the factors.

Laura Feiveson is an economist for the government, a storyteller, and a lifelong enthusiast of math puzzles.  She lives in Washington, DC with her husband and two daughters. 

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Unravel the Mystery: 42 Mind-Bending Math Riddles to Challenge and Entertain You

1. Riddle: Three people check into a hotel room that costs $30. They each contribute $10, handing $30 to the hotel clerk. Later, the hotel clerk realizes there was a mistake and the room only cost $25. The hotel clerk gives $5 to the bellboy to return to the guests. The bellboy, however, decides to keep $2 for himself and gives $1 back to each guest. Now, each guest has paid $9 (a total of $27) and the bellboy kept $2, which adds up to $29. What happened to the missing dollar? 2. Riddle: A snail is at the bottom of a 30-foot well. Each day, the snail climbs up 3 feet, but at night, it slides back down 2 feet. How many days will it take for the snail to reach the top of the well? 3. Riddle: You have 10 stacks of coins with 10 coins in each stack. All the coins in one stack are counterfeit, and all the other coins are genuine. A genuine coin weighs 10 grams, and a counterfeit coin weighs 11 grams. You have a digital scale that you can use only once. How can you determine which stack contains the counterfeit coins? 4. Riddle: What has a hundred legs but cannot stand, a long neck but no head, and is responsible for making everyone late? 5. Riddle: A boy was asked to multiply a certain number by 25. He accidentally multiplied it by 52 instead and got the answer 2600. What was the original number? 6. Riddle: A clock with a regular 12-hour display loses two minutes every hour. It was last set to the correct time at midnight. When the clock shows 6:00 AM, what is the actual time? 7. Riddle: The ages of a father and his son add up to 66 years. The father's age is the son's age reversed. How old are the father and son? 8. Riddle: You have two containers: one holds five liters and the other holds three liters. Using only these containers, how can you measure exactly four liters of water? 9. Riddle: There are 100 light bulbs lined up in a row, all turned off. You start by switching on every second bulb. Then, you go back and toggle every third bulb (turning off if it's on, turning on if it's off). You continue this process with every fourth bulb, every fifth bulb, and so on, until you finish with the 100th bulb. After you've gone through this process, how many light bulbs will be on? 10. Riddle: Two trains are 250 miles apart, traveling toward each other along the same track. Train A travels at 65 miles per hour, and Train B travels at 85 miles per hour. A fly is hovering just above the nose of Train A and decides to fly to Train B. When it reaches Train B, it immediately flies back to Train A. The fly continues this back-and-forth journey until the two trains collide. If the fly travels at 120 miles per hour, how far will it have flown when the trains collide? 11. Riddle: A square room has a width of 8 meters. A spider is located at one of the bottom corners, while a fly is at the diagonally opposite top corner. If the spider can only walk on the walls, ceiling, and floor, what is the shortest distance it must travel to reach the fly? 12. Riddle: A shepherd has 17 sheep. All but nine of them run away. How many sheep does the shepherd have left? 13. Riddle: At a party, everyone shook hands exactly once with every other person present. There were 66 handshakes in total. How many people were at the party? 14. Riddle: I am a three-digit number. My tens digit is five more than my ones digit, and my hundreds digit is eight less than my tens digit. What number am I? 15. Riddle: A man has 53 socks in his drawer: 21 identical blue, 15 identical black, and 17 identical red. The room is dark, and he cannot see the color of the socks. What is the minimum number of socks he must take out of the drawer to guarantee he has a matching pair? 16. Riddle: You have three boxes: one labeled "Apples," another labeled "Oranges," and the third labeled "Apples and Oranges." Each label is placed incorrectly. You are allowed to pick one fruit from one box without looking inside. How can you determine the correct labels for all three boxes? 17. Riddle: A ladder is leaning against a vertical wall, with its bottom 4 feet from the wall. The ladder touches the top of a 6-foot fence that is 2 feet from the wall. How tall is the ladder? 18. Riddle: A man gave one of his five sons a gift of $100. He divided the rest of the money equally among the remaining four sons. If each of the other sons received $80, how much money did the man originally have? 19. Riddle: A gardener plants 100 trees in a perfect square grid, with each tree equidistant from its neighbors. The gardener plants one more tree directly in the center of the square, making the distance between it and each of the four center trees equal to the distance between any two neighboring trees. How many trees are in each row of the square grid? 20. Riddle: In a certain country, half of the people who live there are 25 years old or younger, and ⅔ of the people are 35 years old or younger. What percentage of the population is between 26 and 35 years old? 21. Riddle: A palindrome is a word, phrase, number, or other sequences of characters that reads the same forward and backward. If a number is a palindrome and the sum of its digits is equal to the product of its digits, what is the number? 22. Riddle: A group of people is traveling to a mountain cabin that is 100 miles away. They can travel at an average speed of 50 miles per hour. If they leave at noon, stop halfway for an hour to eat lunch, and then continue to the cabin, what time will they arrive? 23. Riddle: There is a number that is 3 times the sum of its digits. When the digits are reversed, the number increases by 396. What is the number? 24. Riddle: A store is selling apples and oranges at the same price per pound. A customer buys 3 pounds of apples and 5 pounds of oranges for $16. Another customer buys 8 pounds of apples and 2 pounds of oranges for $18. What is the price per pound of apples and oranges? 25. Riddle: A clock chimes 5 times in 4 seconds. How long will it take to chime 12 times? 26. Riddle: A factory produces 500 units of a product every 8 hours. Each unit requires 10 minutes of labor from a worker. How many workers are needed to maintain this production rate? 27. Riddle: A circle with a radius of 10 cm is inscribed in a square. What is the difference between the areas of the square and the circle? 28. Riddle: In a class of 40 students, 12 students play soccer, 14 students play basketball, and 18 students play neither sport. How many students play both soccer and basketball? 29. Riddle: A bus leaves from City A to City B, which is 240 miles away. At the same time, another bus leaves City B to City A. The bus from City A travels at an average speed of 60 miles per hour, while the bus from City B travels at an average speed of 40 miles per hour. At what distance from City A will the two buses meet? 30. Riddle: If a number is divisible by both 9 and 12, it must also be divisible by which other number? 31. Riddle: A person walks up a moving escalator in 60 steps. When the person stands still on the escalator, it takes 90 steps to reach the top. How many steps would the person take if they walked up the non-moving escalator? 32. Riddle: There are 3 consecutive numbers that add up to 57. What are the numbers? 33. Riddle: A man buys a sandwich for $10 and a drink for $5. He gives the cashier a $20 bill. How much change should he receive? 34. Riddle: I am a two-digit number. If you subtract my digits from me, the result is 9. If you add my digits together, the result is also 9. What number am I? 35. Riddle: A train travels 20 miles per hour for 2 hours and then 30 miles per hour for 3 hours. What is the train's average speed during the entire trip? 36. Riddle: A triangle has side lengths of 10 cm, 24 cm, and 26 cm. Is the triangle a right triangle? 37. Riddle: A car rental company charges a flat fee of $20 per day and an additional 15 cents per mile driven. How much will a customer pay if they rent a car for 3 days and drive 150 miles? 38. Riddle: A baker uses 1 cup of sugar for every 2 cups of flour when making a cake. If the baker uses 6 cups of flour, how many cups of sugar are needed? 39. Riddle: At a fruit stand, 5 oranges cost the same as 3 apples. If 15 oranges cost $9, how much do 9 apples cost? 40. Riddle: A number is divisible by 4 and 6. If the number is also divisible by 5, what is the smallest possible value for the number? 41. Riddle: A man gives half of his money to his wife and one-third to his son. He has $200 left. How much money did he originally have? 42. Riddle: A movie theater charges $7 for adults and $5 for children. If 25 people attend a movie and the theater collects $150, how many adults and children attended the movie?