Numbers Riddles

  1. How many times can you subtract the number 5 from 25?
  2. What number can you subtract half from to obtain a result of zero?
  3. How is half of nine four?
  4. What two whole, positive numbers that have a one-digit answer when multiplied and a two-digit answer when added?
  5. What two whole, positive numbers have the same answer when multiplied together as when one is divided by the other?
  6. What two whole, postive numbers have the same answer when multiplied together as when added together?
  7. What two-digit number equals two times the result of multiplying its digits?
  8. What three whole, positive numbers have the same answer when multiplied together as when added together?
  9. What two-digit numbers are each equal to their right-most digit squared?
  10. What is the highest number that can be written with three digits?

Answers: Numbers Riddles Quiz

  1. Once, because after you subtract it's not 25 anymore.
  2. The number 8.  It's made up of two zeros, one on top of the other.
  3. In Roman Numerals, nine is IX and four is IV. If you take IX and cut it in half horizontally, you will get IV.
  4. 1 and 9.
  5. Any number and 1.
  6. 2 and 2.
  7. 36 = 2 x 3 x 6.
  8. 1, 2 and 3.  1 x 2 x 3 = 1 + 2 + 3 = 6
  9. 25 = 5² and 36 = 6².
  10. (9⁹)⁹ = 9³⁸⁷⁴²⁰⁴⁸⁹, which is a number with more than 369 million digits.
  1. Once, because after you subtract it's not 25 anymore.
  2. The number 8.  It's made up of two zeros, one on top of the other.
  3. In Roman Numerals, nine is IX and four is IV. If you take IX and cut it in half horizontally, you will get IV.
  4. 1 and 9.
  5. Any number and 1.
  6. 2 and 2.
  7. 36 = 2 x 3 x 6.
  8. 1, 2 and 3.  1 x 2 x 3 = 1 + 2 + 3 = 6
  9. 25 = 5² and 36 = 6².
  10. (9⁹)⁹ = 9³⁸⁷⁴²⁰⁴⁸⁹, which is a number with more than 369 million digits.