math riddles

50+ Best Math Riddles to Test Your General IQ [2020]

Math riddles are some of the most challenging logic puzzles out there. From a word problem to integers to prime numbers, math brain teasers can be quite frustrating. To get the right answers to math riddles, a person should use logic, critical thinking, and problem solving skills

Getting kids to understand math can be quite hard, but getting them to have fun while learning math is even harder. If you’re a teacher, it’s important for your students–whether if they’re kids or teens and at different levels in math–to challenge themselves, elevate their thinking, and strengthen their math skills

As a teacher, allow your kids to use their lateral thinking by playing math games, or giving them a worksheet of math problems, or adding an easy riddle or two at the end of a quiz every once in a while. 

Here are some fun math riddles to help get your kids to enjoy themselves a little bit more while they learn: 

Math Riddles for Kids and Teens 

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!

You are given 3 positive numbers. You can use addition and multiplication and the answer you get will be the same. Which are the numbers?

1, 2 and 3

When does 11+3=2?

On a clock.

I am a three-digit number. My second digit is 4 times bigger than the third digit. My first digit is 3 less than my second digit. Who am I?

141

If there are three cups of sugar and you take one away, how many do you have?

One cup of sugar. 

Two hens can lay two eggs in two minutes. If this is the maximum speed possible, what is the total number of hen needed to get 500 eggs in 500 minutes?

2 hens.

Ram has 5 sons. Each of his sons has a sister. If so, how many children does Mr. Ram have?

Six. Each son has the same sister.

What do math teachers like to eat?

Pi(e)

What does one math book say to the other math book?

“I have so many problems.”

When you add eight 8’s, the result you get will be number 1,000. How is it possible? You are permitted to use only addition to solve the problem.

888 + 88 + 8 + 8 + 8 = 1,000

What can you put in between 7 and 8 so that the answer is greater than 7 but less than 8? 

A decimal point. 

How did the soccer fan know before the game that the score would be 0-0?

The score is always 0-0 before the game.

Where do fish keep their money?

In the river bank.

If you buy a rooster for the purpose of laying eggs and you expect to get three eggs each day for breakfast, how many eggs will you have after three weeks?

None, roosters do not lay eggs.

10 candles stand burning in a dining room. A strong breeze blows in through an open window and extinguishes 3 of them. Assuming the wind doesn’t extinguish any more candles, how many candles do you have left in the end?

  1. The 7 candles that manage to stay lit will melt down completely. The only candles that remain in the end are the 3 that are extinguished by the wind and therefore stay intact.

I am an EVEN number. If you take away one letter from me, I become odd. What number am I?

SIX – Remove S and it becomes IX – the roman numeral 9

Jess’s pencil was wearing out and is now only 3cm long. Her friend Stan’s brand new pencil was 8 times that length. How long was Stan’s pencil?

8×3 = 24cms

Can you add one mathematical symbol in between 55555 to equal 500?

555-55=500

A mouse wants to get in better shape. She’s going to start by climbing the stairs. Starting on the fourth floor, she climbs up five stories, down seven stories, up six stories, down three stories, and up four stories again. What floor is she on?

The ninth floor

Paul the Polar Bear had a birthday party, with each guest bringing five fish. A nasty little penguin stole two fish but there were still 198 fish left. How many people came to the party?

40

Rico the Rabbit eats 1 carrot on Sunday, 2 carrots on Monday, 4 carrots on Tuesday, and so on. How many carrots does he eat every week?

127 carrots

Ten copycats were sitting in a boat. One jumped out. How many were left?

None. They were copycats so they all jumped out!

Put together Tom and his father and they weigh 280 pounds. Tom’s dad weighs three times as much as he does. How much does Tom weigh?

70 pounds

What two numbers make a one-digit number when you multiply them but a two-digit number when you add them together?

One and nine

How many double-digit numbers are there?

92

If you were born in an odd-numbered year will you celebrate your 50th birthday in an odd or even year?

Odd

Four friends are racing. Lisa finishes four hours ahead of Tony, with Pete finishing eight hours ahead of Max. Max needed six more hours to finish than Lisa. What order do they cross the finish line in?

Pete, Lisa, Tony, Max

16 players enter into a basketball shootout tournament. How many games have to happen before a winner is announced?

15

A baker carries a bag of flour that weighs 15 pounds. He takes half of the flour out, but finds the bag weighs 9 pounds. How heavy is the empty bag?

3 pounds

Math Riddles for Adults 

These math riddles are great for adults or any young person looking to strengthen their skills in the subject. Remember: learning can be fun!

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. 

The combined age of a father and son is 66 years. The age of the father is the age of the son, but with the digits reversed. How old are they?

51 and 15 or 42 and 24 or 60 and 6. 

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.

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

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

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

7.

If you’re 8 feet away from a door and with each move you advance half the distance to the door. How many moves will it take to reach the door? 

You will never reach the door, it will always be half the distance, no matter how small!.

Joe has ten coins totaling $1.19. From these coins, he cannot make exact change for a dollar, half-dollar, quarter, dime, or nickel. What are the coins?

A half-dollar, a quarter, four dimes, and four pennies.

Tom was asked to paint the number of plates on 100 apartments which means he will have to paint numbers 1 through 100. Can you figure out the number of times he will have to paint the number 8?

20 times. (8, 18, 28, 38, 48, 58, 68, 78, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 98)

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

  1. 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).

My twin lives at the reverse of my house number. The difference between our house numbers ends in two. What are the lowest possible numbers of our house?

The lowest possible numbers for our house are 19 and 91.

I am a three-digit number. My tens digit is six more than my ones digit. My hundreds digit is eight less than my tens digit. What number am I?

193

At the time of shipping, Tom can place 10 small boxes or 8 large boxes into a carton. A total of 96 boxes were sent in one shipment. The number of small boxes was less than large boxes. What is the total number of cartons he shipped?

11 cartons

If a zookeeper had 100 pairs of animals in her zoo and if 2 pairs of babies are born for each and every one of the original animals, and then sadly 23 animals don’t survive, how many animals do you have left in total?

977 animals (100×2 = 200; 200+800 = 1000; 1000-23 = 977).

A certain number has three digits. The sum of the three digits equals 36 times this number. Seven times the left digit plus 9 is equal to 5 times the sum of the two other digits. 8 times the second digit minus 9 is equal to the sum of the first and third. What is the number?

324.

Can you arrange four nines to make it equal to 100?

99+9/9 = 100.

 If you see an electric train headed east at 70 an hour but there is a wind blowing in from the west at 80 miles an hour, which way is the smoke from the train going to blow?

An electric train doesn’t have smoke

If days on Mars are as long as two weeks on Earth, how long is an hour?

14 Earth hours

Cara leaves New York at eight in the morning, driving 35 mph. Nancy starts driving to New York at a speed of 50 mph. When they meet a which one will be furthest away from New York?

When they meet, they will be the same distance away from New York

A teacher says that there are fewer than 30 students but more than 20 in a classroom. The children can be divided into groups of two, three, four, six, and eight with no leftovers. How many students are there?

24 students

Seven brothers were born two years apart. The youngest brother is seven. How old is the oldest brother?

19

Difficult Riddles 

These math riddles are so tricky and they can stump any person

IQ Test 

This riddle has gone viral because of how tricky it is. Think you could solve it?

1+4=5
2+5=12
3+6=21
8+11=x 

Answer: 

x=96
(a+b) → (a+ab)

The Snail Problem

A snail is at the bottom of a 20 meters deep pit. Every day the snail climbs 5 meters upwards, but at night it slides 4 meters back downwards. How many days does it take before the snail reaches the top of the pit?

Answer: 

The snail reaches the top of the pit on the 16th day. On the first day, the snail reaches a height of 5 meters and slides down 4 meters at night, and thus ends at a height of 1 meter. And, on the second day, he reaches 6 meters but slides back to 2 meters. On the third day, he reaches 7 meters but slides back to 3 meters. And, on the fifteenth day, he reaches 19 meters but slides back to 15 meters. On the sixteenth day, he reaches 20 meters, so now he is at the top of the pit.

3 Balls

There are 8 balls with 8 different numbers in them: 1, 3, 5, 7, 9, 11, 13, 15. Select 3 balls to equal 30. (Clue: Flip a number!) 

Answer: 

Flip the 9 and turn it into a 6. (There are no rules about the numbers–the question was about the balls!) To the 3 balls are 6, 11, and 13.

Addresses

man who had lived at the highest-numbered address on his street moved to another house on the same street. He noted that the sum of all the addresses below his new address was the same as the sum of all the addresses above his new address. (Every numbered address on the street is used.) He had owned some beautiful brass house numbers and was pleased to discover that he did not have to purchase any new ones. For his new house, he used all of the brass numbers from his previous house. What is his new address?

Old Address: 1681

New Address: 1189

The summation of integers 1 through 1188 is equal to the summation of integers 1190 through 1681. Additionally, the person can reuse their number labels since they both have 1, 1, and 8, and you could flip the 6 upside-down to be the 9.

Science and Math Riddle

Science and math go hand-in-hand, so it would be fitting to include a science-related riddle here. Don’t hurt your brain trying to figure out the answer:

When Manish was three years old he hammered a nail into his favorite tree to mark his height. Six years later at age nine, Manish returned to see how much higher the nail was. If the tree grew by five centimeters each year, how much higher would the nail be?

The nail would be at the same height since trees grow at their tops.

Tricky Math Puzzle

This complicated math brain teaser has stumped tons of people online. In fact, this is one of the hardest math riddles out there and it might be a bit too challenging for kids.

See if you can figure out the answer to this puzzle:

Can you make 24 from the numbers 3, 3, 8, and 8? You can only use the operations + – x / (). You have to use all four numbers.

8/(3 – 8/3) = 24

Did you enjoy these math riddles? Here are some more puzzles to test your smarts:

More Riddles

About the author
January Nelson is a writer, editor, dreamer, and occasional exotic dancer and a collective pen name. Read more articles from January on Thought Catalog.

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