Check out here the list of some number riddles for kids with answers.
Number Riddles [1 to 14]
1. A 300 ft. train is traveling 300 ft. per minute must travel through a 300 ft. long tunnel. How long will it take the train to travel through the tunnel? Answer: Two minutes. It takes the front of the train one minute and the rest of the train will take two minutes to clear the tunnel.
2. A grandmother, two mothers, and two daughters went to a baseball game together and bought one ticket each. How many tickets did they buy in total? Answer: 3 tickets (the grandmother is also a mother and the mother is also a daughter)
3. A little girl goes to the store and buys one dozen eggs. As she is going home, all but three eggs break. How many eggs are left unbroken? Answer: Three
4. A man has 9 children. Half of them are boys. How is this possible? Answer: They are all boys.
5. A word I know, Six letters it contains. Subtract just one, and twelve is what remains. Answer: Dozens
6. Among those numbers whose literal representation in capital letters consist only of straight line segments (for example, FIVE), only one number has a value equal to the number of segments used to write it. What is the number? Answer: 29
Read: Pirate Riddles
7. 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? Answer: 11 cartons. 4 small boxes (410 = 40 boxes) 7 large boxes (78 = 56 boxes). So 96 boxes and 11 total cartons
8. Double my number, I’m less than a score, Half of my number is less than four. Add one to my double when bakers are near, Days of the week are still greater, I fear. Answer: Six
9. Eggs are $0.12 a dozen. How many eggs can you get for a dollar? Answer: 100 eggs, at one penny each
10. How did the soccer fan know before the game that the score would be 0-0? Answer: The score is always 0-0 before the game.
11. How many months of the year have 28 days? Answer: All of them, because every month has at least 28 days.
12. How many times can you subtract the number 5 from 25? Answer: Once, because after you subtract 5 from 25 it becomes 20.
13. I add five to nine, and get two. The answer is correct, but how? Answer: When it is 9am, add 5 hours to it and you will get 2pm.
14. 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? Answer: 141
Number Riddles [15 to 29]
15. I am an odd number. Take away a letter and I become even. What number am I? Answer: Seven
16. If there are three apples and you take away two, how many apples do you have? Answer: You have two apples.
17. If two’s company and three’s a crowd, what are four and five? Answer: 9
18. If you divide thirty by half, and add ten, what do you get? Answer: 70
19. If you multiply this number by any other number, the answer will always be the same. What number is this? Answer: Zero
20. Leon works at the aquarium. When he tries to put each turtle in its own tank, he has one turtle too many. But if he puts two turtles per tank, he has on tank too many. How many turtles and how many tanks does Leon have? Answer: He has 3 tanks and 4 turtles
21. Place three matches on a table. Tell a friend to add two more matches to make eight. Answer: Add two matches to make a roman numeral eight.
22. There is a man with his horse going to town. The man went to the town on Monday. He stayed there for 3 days and then he came back on Friday. How? His horse was not tired, the man wasn’t sleepy. Answer: The horse’s name was Friday.
23. 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? Answer: 20 times. (8, 18, 28, 38, 48, 58, 68, 78, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 98)
24. Using only addition, how can you add eight 8’s to get the number 1,000? Answer: 888 +88 +8 +8 +8 =1,000
25. What can you put between a 7 and an 8 so that the result is greater than a seven, but less than an eight? Answer: A decimal. 7.8 is greater than 7, but less than 8
26. What did one math book say to the other math book? Answer: Do you want to hear my problems?
27. What did the triangle say to the circle? Answer: You’re pointless.
28. What do the numbers 11 and 88 have in common? Answer: They both look the same upside-down and backward.
29. What is the highest number that can be written with three digits? Answer: (9⁹)⁹ = 9³⁸⁷⁴²⁰⁴⁸⁹, which is a number with more than 369 million digits.
Number Riddles [30 to 43]
30. What is the maximum possible number of times you can subtract number 5 from number 25? Answer: Only once. This is because when you subtract 5 from 25 for the first time, it becomes number 20, then 15 and so on.
31. What number can you subtract half from to obtain a result of zero? Answer: The number 8. It’s made up of two zeros, one on top of the other.
32. What three whole, positive numbers have the same answer when multiplied together as when added together? Answer: 1, 2 and 3. 1 x 2 x 3 = 1 + 2 + 3 = 6
33. What two whole, positive numbers have the same answer when multiplied together as when one is divided by the other? Answer: Any number and 1.
34. What two whole, positive numbers that have a one-digit answer when multiplied and a two-digit answer when added? Answer: 1 and 9.
35. What two whole, postive numbers have the same answer when multiplied together as when added together? Answer: 2 and 2.
36. What two-digit number equals two times the result of multiplying its digits? Answer: 36 = 2 x 3 x 6.
37. What two-digit numbers are each equal to their right-most digit squared? Answer: 25 = 5² and 36 = 6².
38. When Miguel was 6 years old, his little sister, Leila, was half is age. If Miguel is 40 years old today, how old is Leila? Answer: She is 37 years old.
39. When things go wrong, what can you always count on? Answer: Your fingers
40. Which is heavier: a ton of bricks or a ton of feathers? Answer: Neither—they both weigh a ton.
41. X is an odd number. Take an alphabet away from X and it becomes even. Which is that number? Answer: Seven (Seven-S=Even)
42. You are given 3 positive numbers. You can add these numbers and multiply them together. The result you get will be the same. Which are the numbers? Answer: 1, 2 and 3
43. You’re sitting down for breakfast and realize you have 4 bagels left. You know you’ll run out in four days so you cut them in half. How many bagels do you have now? Answer: 4 Bagels