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 17. Double it, add 16, halve it, then take away 17. What number do you get?
- 2.Think of 3. Multiply it by 4, then add 8. What number do you end with?
- 3.I thought of a number, added 7 and then doubled it. I got 46. What was my number?
- 4.I thought of a number, added 1 and then doubled it. I got 28. What was my number?
- 5.Think of 10. Multiply it by 4, then add 9. What number do you end with?
- 6.I thought of a number, multiplied it by 3 and added 2. I got 23. What was my number?
- 7.I thought of a number, multiplied it by 2 and added 2. I got 6. What was my number?
- 8.Think of 3. Multiply it by 4, then add 3. What number do you end with?
- 9.I thought of a number, multiplied it by 2 and added 4. I got 26. What was my number?
- 10.Magic trick! Think of 12. Double it, add 8, halve it, then take away 12. What number do you get?
- 11.Think of 3. Multiply it by 2, then add 5. What number do you end with?
- 12.Think of 5. Multiply it by 5, then add 1. What number do you end with?
- 13.I thought of a number, multiplied it by 5 and added 2. I got 72. What was my number?
- 14.Magic trick! Think of 10. Double it, add 18, halve it, then take away 10. What number do you get?
- 15.Think of 4. Multiply it by 2, then add 6. What number do you end with?
- 16.Think of 2. Multiply it by 2, then add 3. What number do you end with?
- 17.I thought of a number, multiplied it by 2 and added 6. I got 14. What was my number?
- 18.I thought of a number, multiplied it by 3 and added 2. I got 41. What was my number?
- 19.Magic trick! Think of 11. Double it, add 10, halve it, then take away 11. What number do you get?
- 20.I thought of a number, multiplied it by 5 and added 4. I got 24. What was my number?
- 21.Magic trick! Think of 19. Double it, add 8, halve it, then take away 19. What number do you get?
- 22.I thought of a number, multiplied it by 4 and added 1. I got 13. What was my number?
- 23.I thought of a number, added 2 and then doubled it. I got 38. What was my number?
- 24.I thought of a number, added 9 and then doubled it. I got 38. What was my number?
- 25.Think of 2. Multiply it by 2, then add 9. What number do you end with?
- 26.I thought of a number, added 3 and then doubled it. I got 46. What was my number?
- 27.I thought of a number, added 7 and then doubled it. I got 30. What was my number?
- 28.Think of 5. Multiply it by 4, then add 7. What number do you end with?
- 29.Magic trick! Think of 18. Double it, add 8, halve it, then take away 18. What number do you get?
- 30.I thought of a number, multiplied it by 3 and added 3. I got 30. What was my number?
- 31.I thought of a number, added 2 and then doubled it. I got 36. What was my number?
- 32.I thought of a number, multiplied it by 4 and added 8. I got 48. What was my number?
- 33.Think of 11. Multiply it by 2, then add 9. What number do you end with?
- 34.Magic trick! Think of 6. Double it, add 6, halve it, then take away 6. What number do you get?
- 35.I thought of a number, multiplied it by 2 and added 7. I got 35. What was my number?
- 36.I thought of a number, added 3 and then doubled it. I got 32. What was my number?
- 37.I thought of a number, multiplied it by 2 and added 2. I got 16. What was my number?
- 38.I thought of a number, multiplied it by 5 and added 6. I got 81. What was my number?
- 39.I thought of a number, multiplied it by 2 and added 9. I got 25. What was my number?
- 40.Think of 10. Multiply it by 4, then add 3. What number do you end with?
Answer key
- 8
- 20
- 16
- 13
- 49
- 7
- 2
- 15
- 11
- 4
- 11
- 26
- 14
- 9
- 14
- 7
- 4
- 13
- 5
- 4
- 4
- 3
- 17
- 10
- 13
- 20
- 8
- 27
- 4
- 9
- 16
- 10
- 31
- 3
- 14
- 13
- 7
- 15
- 8
- 43
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks