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 16. Double it, add 4, halve it, then take away 16. What number do you get?
- 2.Think of 6. Multiply it by 4, then add 1. What number do you end with?
- 3.I thought of a number, added 1 and then doubled it. I got 16. What was my number?
- 4.I thought of a number, multiplied it by 3 and added 4. I got 46. What was my number?
- 5.Magic trick! Think of 14. Double it, add 14, halve it, then take away 14. What number do you get?
- 6.I thought of a number, added 1 and then doubled it. I got 28. What was my number?
- 7.I thought of a number, added 4 and then doubled it. I got 22. What was my number?
- 8.I thought of a number, added 4 and then doubled it. I got 32. What was my number?
- 9.Think of 15. Multiply it by 5, then add 6. What number do you end with?
- 10.I thought of a number, multiplied it by 2 and added 6. I got 30. What was my number?
- 11.I thought of a number, added 8 and then doubled it. I got 38. What was my number?
- 12.Think of 2. Multiply it by 3, then add 5. 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.I thought of a number, added 1 and then doubled it. I got 10. What was my number?
- 15.Magic trick! Think of 11. Double it, add 6, halve it, then take away 11. What number do you get?
- 16.Magic trick! Think of 2. Double it, add 12, halve it, then take away 2. What number do you get?
- 17.Think of 3. Multiply it by 2, then add 8. What number do you end with?
- 18.I thought of a number, added 1 and then doubled it. I got 12. What was my number?
- 19.I thought of a number, added 8 and then doubled it. I got 52. What was my number?
- 20.I thought of a number, multiplied it by 2 and added 7. I got 17. What was my number?
- 21.Think of 5. Multiply it by 5, then add 8. What number do you end with?
- 22.Think of 9. Multiply it by 2, then add 2. What number do you end with?
- 23.Think of 11. Multiply it by 2, then add 3. What number do you end with?
- 24.Think of 12. Multiply it by 5, then add 6. What number do you end with?
- 25.Think of 3. Multiply it by 4, then add 9. What number do you end with?
- 26.I thought of a number, added 6 and then doubled it. I got 34. What was my number?
- 27.Think of 4. Multiply it by 2, then add 5. What number do you end with?
- 28.Think of 4. Multiply it by 4, then add 7. What number do you end with?
- 29.Magic trick! Think of 5. Double it, add 10, halve it, then take away 5. What number do you get?
- 30.Magic trick! Think of 4. Double it, add 8, halve it, then take away 4. What number do you get?
- 31.Magic trick! Think of 4. Double it, add 6, halve it, then take away 4. What number do you get?
- 32.Magic trick! Think of 5. Double it, add 8, halve it, then take away 5. What number do you get?
- 33.Magic trick! Think of 3. Double it, add 4, halve it, then take away 3. What number do you get?
- 34.I thought of a number, multiplied it by 5 and added 9. I got 49. What was my number?
- 35.Think of 12. Multiply it by 5, then add 2. What number do you end with?
- 36.I thought of a number, added 1 and then doubled it. I got 42. What was my number?
- 37.I thought of a number, added 9 and then doubled it. I got 40. What was my number?
- 38.Magic trick! Think of 13. Double it, add 14, halve it, then take away 13. What number do you get?
- 39.I thought of a number, added 6 and then doubled it. I got 18. What was my number?
- 40.I thought of a number, added 6 and then doubled it. I got 32. What was my number?
Answer key
- 2
- 25
- 7
- 14
- 7
- 13
- 7
- 12
- 81
- 12
- 11
- 11
- 14
- 4
- 3
- 6
- 14
- 5
- 18
- 5
- 33
- 20
- 25
- 66
- 21
- 11
- 13
- 23
- 5
- 4
- 3
- 4
- 2
- 8
- 62
- 20
- 11
- 7
- 3
- 10
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks