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.Magic trick! Think of 18. Double it, add 16, halve it, then take away 18. What number do you get?
- 2.Magic trick! Think of 19. Double it, add 8, halve it, then take away 19. What number do you get?
- 3.I thought of a number, multiplied it by 2 and added 2. I got 8. What was my number?
- 4.Magic trick! Think of 12. Double it, add 4, halve it, then take away 12. What number do you get?
- 5.I thought of a number, multiplied it by 4 and added 4. I got 24. What was my number?
- 6.Magic trick! Think of 20. Double it, add 16, halve it, then take away 20. What number do you get?
- 7.I thought of a number, multiplied it by 3 and added 3. I got 15. What was my number?
- 8.Magic trick! Think of 10. Double it, add 12, halve it, then take away 10. What number do you get?
- 9.I thought of a number, added 9 and then doubled it. I got 36. What was my number?
- 10.Magic trick! Think of 7. Double it, add 4, halve it, then take away 7. What number do you get?
- 11.I thought of a number, added 4 and then doubled it. I got 48. What was my number?
- 12.I thought of a number, added 6 and then doubled it. I got 42. What was my number?
- 13.Magic trick! Think of 19. Double it, add 14, halve it, then take away 19. What number do you get?
- 14.Think of 5. Multiply it by 3, then add 9. What number do you end with?
- 15.Think of 11. Multiply it by 4, then add 1. What number do you end with?
- 16.I thought of a number, added 5 and then doubled it. I got 36. What was my number?
- 17.I thought of a number, multiplied it by 3 and added 2. I got 8. What was my number?
- 18.I thought of a number, multiplied it by 3 and added 9. I got 48. What was my number?
- 19.I thought of a number, added 6 and then doubled it. I got 26. What was my number?
- 20.Magic trick! Think of 2. Double it, add 16, halve it, then take away 2. What number do you get?
- 21.Magic trick! Think of 4. Double it, add 10, halve it, then take away 4. What number do you get?
- 22.Think of 14. Multiply it by 4, then add 5. What number do you end with?
- 23.I thought of a number, multiplied it by 2 and added 5. I got 21. What was my number?
- 24.Think of 2. Multiply it by 2, then add 1. What number do you end with?
- 25.Think of 10. Multiply it by 3, then add 2. What number do you end with?
- 26.Magic trick! Think of 11. Double it, add 16, halve it, then take away 11. What number do you get?
- 27.I thought of a number, added 1 and then doubled it. I got 28. What was my number?
- 28.Think of 8. Multiply it by 3, then add 1. What number do you end with?
- 29.Think of 15. Multiply it by 4, then add 7. What number do you end with?
- 30.I thought of a number, multiplied it by 2 and added 2. I got 24. What was my number?
- 31.I thought of a number, multiplied it by 5 and added 4. I got 64. What was my number?
- 32.I thought of a number, multiplied it by 3 and added 1. I got 10. What was my number?
- 33.I thought of a number, added 8 and then doubled it. I got 26. What was my number?
- 34.Think of 11. Multiply it by 5, then add 5. What number do you end with?
- 35.I thought of a number, added 9 and then doubled it. I got 48. What was my number?
- 36.Think of 13. Multiply it by 3, then add 1. What number do you end with?
- 37.Think of 12. Multiply it by 2, then add 6. What number do you end with?
- 38.I thought of a number, multiplied it by 4 and added 4. I got 20. What was my number?
- 39.I thought of a number, multiplied it by 5 and added 7. I got 32. What was my number?
- 40.Magic trick! Think of 7. Double it, add 10, halve it, then take away 7. What number do you get?
Answer key
- 8
- 4
- 3
- 2
- 5
- 8
- 4
- 6
- 9
- 2
- 20
- 15
- 7
- 24
- 45
- 13
- 2
- 13
- 7
- 8
- 5
- 61
- 8
- 5
- 32
- 8
- 13
- 25
- 67
- 11
- 12
- 3
- 5
- 60
- 15
- 40
- 30
- 4
- 5
- 5
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks