Think of a Number Puzzles Worksheet
The trick (Undo the steps): Going forwards: do the steps in order. Going backwards: start from the result and undo each step, last one first. Undo + with −, × with ÷, and doubling with halving.
NameDateTime takenScore ___ / 40
- 1.I thought of a number, multiplied it by 5 and added 9. I got 19. What was my number?
- 2.I thought of a number, added 8 and then doubled it. I got 28. What was my number?
- 3.Think of 4. Multiply it by 2, then add 4. What number do you end with?
- 4.I thought of a number, multiplied it by 4 and added 2. I got 10. What was my number?
- 5.Magic trick! Think of 6. Double it, add 10, halve it, then take away 6. What number do you get?
- 6.Magic trick! Think of 13. Double it, add 10, halve it, then take away 13. What number do you get?
- 7.Think of 5. Multiply it by 4, then add 2. What number do you end with?
- 8.I thought of a number, multiplied it by 4 and added 1. I got 41. What was my number?
- 9.Magic trick! Think of 7. Double it, add 6, halve it, then take away 7. What number do you get?
- 10.I thought of a number, multiplied it by 4 and added 5. I got 21. What was my number?
- 11.Think of 3. Multiply it by 2, then add 4. What number do you end with?
- 12.I thought of a number, multiplied it by 5 and added 7. I got 52. What was my number?
- 13.Think of 4. Multiply it by 4, then add 1. What number do you end with?
- 14.Magic trick! Think of 4. Double it, add 12, halve it, then take away 4. What number do you get?
- 15.Magic trick! Think of 20. Double it, add 10, halve it, then take away 20. What number do you get?
- 16.Magic trick! Think of 10. Double it, add 12, halve it, then take away 10. What number do you get?
- 17.I thought of a number, multiplied it by 4 and added 4. I got 20. What was my number?
- 18.I thought of a number, multiplied it by 3 and added 7. I got 37. What was my number?
- 19.I thought of a number, multiplied it by 3 and added 3. I got 45. What was my number?
- 20.Think of 6. Multiply it by 2, then add 3. What number do you end with?
- 21.I thought of a number, added 2 and then doubled it. I got 28. What was my number?
- 22.I thought of a number, added 9 and then doubled it. I got 36. What was my number?
- 23.Think of 10. Multiply it by 2, then add 4. What number do you end with?
- 24.Magic trick! Think of 19. Double it, add 6, halve it, then take away 19. What number do you get?
- 25.I thought of a number, added 1 and then doubled it. I got 24. What was my number?
- 26.I thought of a number, multiplied it by 2 and added 1. I got 27. What was my number?
- 27.Think of 5. Multiply it by 5, then add 2. What number do you end with?
- 28.I thought of a number, added 1 and then doubled it. I got 22. What was my number?
- 29.I thought of a number, added 9 and then doubled it. I got 30. What was my number?
- 30.Magic trick! Think of 13. Double it, add 8, halve it, then take away 13. What number do you get?
- 31.I thought of a number, multiplied it by 5 and added 1. I got 26. What was my number?
- 32.I thought of a number, added 3 and then doubled it. I got 46. What was my number?
- 33.Magic trick! Think of 4. Double it, add 14, halve it, then take away 4. What number do you get?
- 34.Think of 6. Multiply it by 3, then add 6. What number do you end with?
- 35.I thought of a number, multiplied it by 5 and added 3. I got 73. What was my number?
- 36.Magic trick! Think of 11. Double it, add 6, halve it, then take away 11. What number do you get?
- 37.I thought of a number, added 7 and then doubled it. I got 40. What was my number?
- 38.Think of 2. Multiply it by 3, then add 8. What number do you end with?
- 39.I thought of a number, multiplied it by 2 and added 1. I got 29. What was my number?
- 40.I thought of a number, multiplied it by 3 and added 2. I got 29. What was my number?
Answer key
- 2
- 6
- 12
- 2
- 5
- 5
- 22
- 10
- 3
- 4
- 10
- 9
- 17
- 6
- 5
- 6
- 4
- 10
- 14
- 15
- 12
- 9
- 24
- 3
- 11
- 13
- 27
- 10
- 6
- 4
- 5
- 20
- 7
- 24
- 14
- 3
- 13
- 14
- 14
- 9
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks