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 10. Double it, add 4, halve it, then take away 10. What number do you get?
- 2.Think of 8. Multiply it by 5, then add 5. What number do you end with?
- 3.Think of 9. Multiply it by 2, then add 2. What number do you end with?
- 4.I thought of a number, added 9 and then doubled it. I got 26. What was my number?
- 5.Think of 4. Multiply it by 2, then add 8. What number do you end with?
- 6.I thought of a number, multiplied it by 2 and added 4. I got 16. What was my number?
- 7.Magic trick! Think of 2. Double it, add 4, halve it, then take away 2. What number do you get?
- 8.Magic trick! Think of 19. Double it, add 12, halve it, then take away 19. What number do you get?
- 9.I thought of a number, added 7 and then doubled it. I got 42. What was my number?
- 10.Think of 12. Multiply it by 4, then add 8. What number do you end with?
- 11.Think of 7. Multiply it by 4, then add 7. What number do you end with?
- 12.I thought of a number, multiplied it by 2 and added 6. I got 22. What was my number?
- 13.Magic trick! Think of 7. Double it, add 14, halve it, then take away 7. What number do you get?
- 14.I thought of a number, multiplied it by 4 and added 3. I got 43. What was my number?
- 15.I thought of a number, added 1 and then doubled it. I got 22. What was my number?
- 16.Think of 8. Multiply it by 3, then add 5. What number do you end with?
- 17.Think of 5. Multiply it by 5, then add 5. What number do you end with?
- 18.I thought of a number, added 3 and then doubled it. I got 14. What was my number?
- 19.I thought of a number, multiplied it by 2 and added 1. I got 17. What was my number?
- 20.Magic trick! Think of 17. Double it, add 16, halve it, then take away 17. What number do you get?
- 21.I thought of a number, added 4 and then doubled it. I got 32. What was my number?
- 22.I thought of a number, added 4 and then doubled it. I got 48. What was my number?
- 23.I thought of a number, added 5 and then doubled it. I got 22. What was my number?
- 24.Magic trick! Think of 11. Double it, add 16, halve it, then take away 11. What number do you get?
- 25.Think of 12. Multiply it by 2, then add 2. What number do you end with?
- 26.I thought of a number, multiplied it by 3 and added 5. I got 23. What was my number?
- 27.Magic trick! Think of 3. Double it, add 8, halve it, then take away 3. What number do you get?
- 28.Magic trick! Think of 3. Double it, add 6, halve it, then take away 3. What number do you get?
- 29.Magic trick! Think of 3. Double it, add 10, halve it, then take away 3. What number do you get?
- 30.I thought of a number, multiplied it by 4 and added 5. I got 45. What was my number?
- 31.I thought of a number, added 1 and then doubled it. I got 12. What was my number?
- 32.I thought of a number, added 3 and then doubled it. I got 36. What was my number?
- 33.I thought of a number, multiplied it by 4 and added 7. I got 19. What was my number?
- 34.Think of 10. Multiply it by 4, then add 8. What number do you end with?
- 35.I thought of a number, multiplied it by 3 and added 6. I got 21. What was my number?
- 36.Magic trick! Think of 2. Double it, add 16, halve it, then take away 2. What number do you get?
- 37.Magic trick! Think of 20. Double it, add 6, halve it, then take away 20. What number do you get?
- 38.I thought of a number, added 1 and then doubled it. I got 16. What was my number?
- 39.I thought of a number, multiplied it by 3 and added 1. I got 46. What was my number?
- 40.I thought of a number, multiplied it by 2 and added 6. I got 16. What was my number?
Answer key
- 2
- 45
- 20
- 4
- 16
- 6
- 2
- 6
- 14
- 56
- 35
- 8
- 7
- 10
- 10
- 29
- 30
- 4
- 8
- 8
- 12
- 20
- 6
- 8
- 26
- 6
- 4
- 3
- 5
- 10
- 5
- 15
- 3
- 48
- 5
- 8
- 3
- 7
- 15
- 5
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks