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 6. Multiply it by 5, then add 8. What number do you end with?
- 2.I thought of a number, added 6 and then doubled it. I got 30. What was my number?
- 3.I thought of a number, multiplied it by 3 and added 4. I got 22. What was my number?
- 4.I thought of a number, added 4 and then doubled it. I got 16. What was my number?
- 5.Magic trick! Think of 20. Double it, add 18, halve it, then take away 20. What number do you get?
- 6.I thought of a number, added 8 and then doubled it. I got 32. What was my number?
- 7.Think of 8. Multiply it by 3, then add 9. What number do you end with?
- 8.Think of 12. Multiply it by 4, then add 9. What number do you end with?
- 9.I thought of a number, added 7 and then doubled it. I got 20. What was my number?
- 10.Magic trick! Think of 4. Double it, add 4, halve it, then take away 4. What number do you get?
- 11.Magic trick! Think of 2. Double it, add 12, halve it, then take away 2. What number do you get?
- 12.Magic trick! Think of 5. Double it, add 12, halve it, then take away 5. What number do you get?
- 13.I thought of a number, multiplied it by 2 and added 5. I got 13. What was my number?
- 14.I thought of a number, added 5 and then doubled it. I got 48. What was my number?
- 15.Magic trick! Think of 8. Double it, add 4, halve it, then take away 8. What number do you get?
- 16.Think of 9. Multiply it by 5, then add 2. What number do you end with?
- 17.I thought of a number, added 7 and then doubled it. I got 54. What was my number?
- 18.Magic trick! Think of 14. Double it, add 18, halve it, then take away 14. What number do you get?
- 19.I thought of a number, added 2 and then doubled it. I got 24. What was my number?
- 20.Magic trick! Think of 19. Double it, add 14, halve it, then take away 19. What number do you get?
- 21.I thought of a number, added 7 and then doubled it. I got 30. What was my number?
- 22.I thought of a number, added 8 and then doubled it. I got 26. What was my number?
- 23.Think of 11. Multiply it by 4, then add 3. What number do you end with?
- 24.I thought of a number, multiplied it by 2 and added 3. I got 23. What was my number?
- 25.I thought of a number, added 5 and then doubled it. I got 38. What was my number?
- 26.Magic trick! Think of 3. Double it, add 12, halve it, then take away 3. What number do you get?
- 27.I thought of a number, multiplied it by 2 and added 9. I got 27. What was my number?
- 28.I thought of a number, added 3 and then doubled it. I got 30. What was my number?
- 29.Magic trick! Think of 3. Double it, add 14, halve it, then take away 3. What number do you get?
- 30.Magic trick! Think of 18. Double it, add 4, halve it, then take away 18. What number do you get?
- 31.Magic trick! Think of 19. Double it, add 6, halve it, then take away 19. What number do you get?
- 32.Magic trick! Think of 19. Double it, add 4, halve it, then take away 19. What number do you get?
- 33.Think of 13. Multiply it by 2, then add 1. What number do you end with?
- 34.I thought of a number, added 2 and then doubled it. I got 44. What was my number?
- 35.Magic trick! Think of 13. Double it, add 4, halve it, then take away 13. What number do you get?
- 36.Think of 7. Multiply it by 4, then add 1. What number do you end with?
- 37.I thought of a number, added 3 and then doubled it. I got 42. What was my number?
- 38.I thought of a number, added 8 and then doubled it. I got 28. What was my number?
- 39.I thought of a number, multiplied it by 2 and added 8. I got 18. What was my number?
- 40.I thought of a number, added 5 and then doubled it. I got 30. What was my number?
Answer key
- 38
- 9
- 6
- 4
- 9
- 8
- 33
- 57
- 3
- 2
- 6
- 6
- 4
- 19
- 2
- 47
- 20
- 9
- 10
- 7
- 8
- 5
- 47
- 10
- 14
- 6
- 9
- 12
- 7
- 2
- 3
- 2
- 27
- 20
- 2
- 29
- 18
- 6
- 5
- 10
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks