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.I thought of a number, added 4 and then doubled it. I got 14. What was my number?
- 2.I thought of a number, added 8 and then doubled it. I got 50. What was my number?
- 3.I thought of a number, multiplied it by 2 and added 9. I got 33. What was my number?
- 4.Magic trick! Think of 7. Double it, add 6, halve it, then take away 7. What number do you get?
- 5.Think of 10. Multiply it by 5, then add 3. What number do you end with?
- 6.I thought of a number, added 1 and then doubled it. I got 18. What was my number?
- 7.Magic trick! Think of 6. Double it, add 6, halve it, then take away 6. What number do you get?
- 8.I thought of a number, multiplied it by 4 and added 3. I got 39. What was my number?
- 9.Think of 14. Multiply it by 5, then add 7. What number do you end with?
- 10.I thought of a number, multiplied it by 2 and added 7. I got 25. What was my number?
- 11.Magic trick! Think of 11. Double it, add 4, halve it, then take away 11. What number do you get?
- 12.Think of 7. Multiply it by 5, then add 7. What number do you end with?
- 13.I thought of a number, added 8 and then doubled it. I got 36. What was my number?
- 14.I thought of a number, added 7 and then doubled it. I got 44. What was my number?
- 15.I thought of a number, multiplied it by 3 and added 9. I got 21. What was my number?
- 16.Magic trick! Think of 7. Double it, add 14, halve it, then take away 7. What number do you get?
- 17.Think of 11. Multiply it by 3, then add 1. What number do you end with?
- 18.I thought of a number, added 1 and then doubled it. I got 20. What was my number?
- 19.Think of 6. Multiply it by 5, then add 6. What number do you end with?
- 20.I thought of a number, added 5 and then doubled it. I got 48. What was my number?
- 21.Magic trick! Think of 14. Double it, add 8, halve it, then take away 14. What number do you get?
- 22.I thought of a number, added 9 and then doubled it. I got 48. What was my number?
- 23.I thought of a number, added 4 and then doubled it. I got 38. What was my number?
- 24.I thought of a number, multiplied it by 2 and added 5. I got 31. What was my number?
- 25.Think of 6. Multiply it by 4, then add 7. What number do you end with?
- 26.I thought of a number, added 4 and then doubled it. I got 22. What was my number?
- 27.Magic trick! Think of 2. Double it, add 6, halve it, then take away 2. What number do you get?
- 28.Magic trick! Think of 9. Double it, add 14, halve it, then take away 9. What number do you get?
- 29.I thought of a number, multiplied it by 3 and added 9. I got 54. What was my number?
- 30.I thought of a number, added 5 and then doubled it. I got 46. What was my number?
- 31.Magic trick! Think of 14. Double it, add 6, halve it, then take away 14. What number do you get?
- 32.Magic trick! Think of 14. Double it, add 14, halve it, then take away 14. What number do you get?
- 33.Magic trick! Think of 9. Double it, add 8, halve it, then take away 9. What number do you get?
- 34.Magic trick! Think of 12. Double it, add 8, halve it, then take away 12. What number do you get?
- 35.I thought of a number, multiplied it by 2 and added 3. I got 23. What was my number?
- 36.I thought of a number, multiplied it by 2 and added 8. I got 16. What was my number?
- 37.I thought of a number, multiplied it by 3 and added 5. I got 32. What was my number?
- 38.Think of 5. Multiply it by 2, then add 8. What number do you end with?
- 39.Magic trick! Think of 13. Double it, add 12, halve it, then take away 13. What number do you get?
- 40.I thought of a number, multiplied it by 4 and added 1. I got 53. What was my number?
Answer key
- 3
- 17
- 12
- 3
- 53
- 8
- 3
- 9
- 77
- 9
- 2
- 42
- 10
- 15
- 4
- 7
- 34
- 9
- 36
- 19
- 4
- 15
- 15
- 13
- 31
- 7
- 3
- 7
- 15
- 18
- 3
- 7
- 4
- 4
- 10
- 4
- 9
- 18
- 6
- 13
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks