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.Think of 12. Multiply it by 4, then add 7. What number do you end with?
- 2.Magic trick! Think of 10. Double it, add 12, halve it, then take away 10. What number do you get?
- 3.Think of 13. Multiply it by 5, then add 4. What number do you end with?
- 4.Think of 3. Multiply it by 4, then add 1. What number do you end with?
- 5.I thought of a number, added 2 and then doubled it. I got 24. What was my number?
- 6.I thought of a number, added 9 and then doubled it. I got 36. What was my number?
- 7.I thought of a number, added 1 and then doubled it. I got 8. What was my number?
- 8.I thought of a number, added 9 and then doubled it. I got 40. What was my number?
- 9.Magic trick! Think of 13. Double it, add 8, halve it, then take away 13. What number do you get?
- 10.Think of 11. Multiply it by 3, then add 3. What number do you end with?
- 11.Magic trick! Think of 4. Double it, add 18, halve it, then take away 4. What number do you get?
- 12.Think of 14. Multiply it by 4, then add 5. What number do you end with?
- 13.Magic trick! Think of 7. Double it, add 8, halve it, then take away 7. What number do you get?
- 14.Think of 3. Multiply it by 2, then add 1. What number do you end with?
- 15.I thought of a number, multiplied it by 4 and added 9. I got 49. What was my number?
- 16.Think of 15. Multiply it by 4, then add 1. What number do you end with?
- 17.I thought of a number, added 9 and then doubled it. I got 56. What was my number?
- 18.Magic trick! Think of 2. Double it, add 10, halve it, then take away 2. What number do you get?
- 19.Think of 2. Multiply it by 2, then add 9. What number do you end with?
- 20.I thought of a number, added 2 and then doubled it. I got 42. What was my number?
- 21.I thought of a number, multiplied it by 4 and added 1. I got 25. What was my number?
- 22.Magic trick! Think of 15. Double it, add 14, halve it, then take away 15. What number do you get?
- 23.Magic trick! Think of 12. Double it, add 6, halve it, then take away 12. What number do you get?
- 24.I thought of a number, multiplied it by 5 and added 6. I got 66. What was my number?
- 25.Think of 2. Multiply it by 5, then add 2. What number do you end with?
- 26.I thought of a number, added 1 and then doubled it. I got 40. What was my number?
- 27.Magic trick! Think of 19. Double it, add 4, halve it, then take away 19. What number do you get?
- 28.Think of 5. Multiply it by 3, then add 5. What number do you end with?
- 29.I thought of a number, added 1 and then doubled it. I got 24. What was my number?
- 30.Think of 5. Multiply it by 5, then add 5. What number do you end with?
- 31.I thought of a number, multiplied it by 3 and added 7. I got 13. What was my number?
- 32.I thought of a number, added 3 and then doubled it. I got 18. What was my number?
- 33.I thought of a number, multiplied it by 4 and added 5. I got 29. What was my number?
- 34.Magic trick! Think of 17. Double it, add 8, halve it, then take away 17. What number do you get?
- 35.I thought of a number, multiplied it by 4 and added 2. I got 10. What was my number?
- 36.I thought of a number, added 8 and then doubled it. I got 44. What was my number?
- 37.Think of 15. Multiply it by 3, then add 8. What number do you end with?
- 38.I thought of a number, multiplied it by 2 and added 3. I got 29. What was my number?
- 39.I thought of a number, multiplied it by 4 and added 9. I got 45. What was my number?
- 40.Think of 2. Multiply it by 3, then add 2. What number do you end with?
Answer key
- 55
- 6
- 69
- 13
- 10
- 9
- 3
- 11
- 4
- 36
- 9
- 61
- 4
- 7
- 10
- 61
- 19
- 5
- 13
- 19
- 6
- 7
- 3
- 12
- 12
- 19
- 2
- 20
- 11
- 30
- 2
- 6
- 6
- 4
- 2
- 14
- 53
- 13
- 9
- 8
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks