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, multiplied it by 4 and added 1. I got 57. What was my number?
- 2.Think of 8. Multiply it by 4, then add 1. What number do you end with?
- 3.I thought of a number, multiplied it by 2 and added 6. I got 16. What was my number?
- 4.Magic trick! Think of 17. Double it, add 16, halve it, then take away 17. What number do you get?
- 5.Think of 11. Multiply it by 3, then add 1. What number do you end with?
- 6.Think of 15. Multiply it by 2, then add 6. What number do you end with?
- 7.I thought of a number, added 5 and then doubled it. I got 44. What was my number?
- 8.Magic trick! Think of 4. Double it, add 18, halve it, then take away 4. What number do you get?
- 9.Magic trick! Think of 11. Double it, add 12, halve it, then take away 11. What number do you get?
- 10.I thought of a number, added 1 and then doubled it. I got 24. What was my number?
- 11.Think of 3. Multiply it by 3, then add 1. What number do you end with?
- 12.Magic trick! Think of 14. Double it, add 8, halve it, then take away 14. What number do you get?
- 13.I thought of a number, added 5 and then doubled it. I got 28. What was my number?
- 14.I thought of a number, added 1 and then doubled it. I got 10. What was my number?
- 15.Magic trick! Think of 16. Double it, add 8, halve it, then take away 16. What number do you get?
- 16.I thought of a number, added 1 and then doubled it. I got 40. What was my number?
- 17.Think of 13. Multiply it by 2, then add 9. What number do you end with?
- 18.I thought of a number, multiplied it by 4 and added 3. I got 47. What was my number?
- 19.Think of 7. Multiply it by 5, then add 4. What number do you end with?
- 20.I thought of a number, multiplied it by 3 and added 3. I got 24. What was my number?
- 21.I thought of a number, multiplied it by 4 and added 6. I got 54. What was my number?
- 22.Think of 2. Multiply it by 5, then add 5. What number do you end with?
- 23.Think of 12. Multiply it by 2, then add 7. What number do you end with?
- 24.I thought of a number, multiplied it by 2 and added 2. I got 22. What was my number?
- 25.Think of 4. Multiply it by 4, then add 9. What number do you end with?
- 26.I thought of a number, added 9 and then doubled it. I got 50. What was my number?
- 27.Magic trick! Think of 9. Double it, add 4, halve it, then take away 9. What number do you get?
- 28.I thought of a number, added 1 and then doubled it. I got 28. What was my number?
- 29.I thought of a number, added 7 and then doubled it. I got 32. What was my number?
- 30.Magic trick! Think of 12. Double it, add 14, halve it, then take away 12. What number do you get?
- 31.Think of 2. Multiply it by 2, then add 2. What number do you end with?
- 32.I thought of a number, multiplied it by 4 and added 9. I got 41. What was my number?
- 33.I thought of a number, added 3 and then doubled it. I got 12. What was my number?
- 34.I thought of a number, multiplied it by 5 and added 3. I got 73. What was my number?
- 35.Magic trick! Think of 8. Double it, add 4, halve it, then take away 8. What number do you get?
- 36.Magic trick! Think of 7. Double it, add 18, halve it, then take away 7. What number do you get?
- 37.I thought of a number, added 5 and then doubled it. I got 22. What was my number?
- 38.I thought of a number, added 5 and then doubled it. I got 40. What was my number?
- 39.Magic trick! Think of 6. Double it, add 10, halve it, then take away 6. What number do you get?
- 40.I thought of a number, added 4 and then doubled it. I got 48. What was my number?
Answer key
- 14
- 33
- 5
- 8
- 34
- 36
- 17
- 9
- 6
- 11
- 10
- 4
- 9
- 4
- 4
- 19
- 35
- 11
- 39
- 7
- 12
- 15
- 31
- 10
- 25
- 16
- 2
- 13
- 9
- 7
- 6
- 8
- 3
- 14
- 2
- 9
- 6
- 15
- 5
- 20
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks