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 2. Double it, add 6, halve it, then take away 2. What number do you get?
- 2.Think of 10. Multiply it by 2, then add 8. What number do you end with?
- 3.Think of 14. Multiply it by 5, then add 3. What number do you end with?
- 4.I thought of a number, added 9 and then doubled it. I got 30. What was my number?
- 5.I thought of a number, multiplied it by 5 and added 1. I got 51. What was my number?
- 6.I thought of a number, multiplied it by 3 and added 1. I got 43. What was my number?
- 7.Magic trick! Think of 3. Double it, add 10, halve it, then take away 3. What number do you get?
- 8.I thought of a number, added 6 and then doubled it. I got 22. What was my number?
- 9.Magic trick! Think of 12. Double it, add 18, halve it, then take away 12. What number do you get?
- 10.Magic trick! Think of 14. Double it, add 6, halve it, then take away 14. What number do you get?
- 11.I thought of a number, multiplied it by 3 and added 3. I got 12. What was my number?
- 12.Magic trick! Think of 6. Double it, add 18, halve it, then take away 6. What number do you get?
- 13.Magic trick! Think of 18. Double it, add 16, halve it, then take away 18. What number do you get?
- 14.I thought of a number, multiplied it by 4 and added 7. I got 27. What was my number?
- 15.I thought of a number, added 7 and then doubled it. I got 42. What was my number?
- 16.I thought of a number, added 6 and then doubled it. I got 34. What was my number?
- 17.I thought of a number, added 1 and then doubled it. I got 12. What was my number?
- 18.Magic trick! Think of 5. Double it, add 4, halve it, then take away 5. What number do you get?
- 19.Think of 9. Multiply it by 2, then add 5. What number do you end with?
- 20.I thought of a number, added 7 and then doubled it. I got 22. What was my number?
- 21.I thought of a number, multiplied it by 5 and added 5. I got 80. What was my number?
- 22.Magic trick! Think of 11. Double it, add 14, halve it, then take away 11. What number do you get?
- 23.I thought of a number, added 9 and then doubled it. I got 24. What was my number?
- 24.Magic trick! Think of 15. Double it, add 8, halve it, then take away 15. What number do you get?
- 25.Magic trick! Think of 6. Double it, add 4, halve it, then take away 6. What number do you get?
- 26.I thought of a number, added 3 and then doubled it. I got 26. What was my number?
- 27.Magic trick! Think of 18. Double it, add 12, halve it, then take away 18. What number do you get?
- 28.Think of 8. Multiply it by 2, then add 5. What number do you end with?
- 29.Think of 12. Multiply it by 3, then add 7. What number do you end with?
- 30.Think of 10. Multiply it by 4, then add 8. What number do you end with?
- 31.I thought of a number, multiplied it by 5 and added 1. I got 26. What was my number?
- 32.Think of 13. Multiply it by 5, then add 1. What number do you end with?
- 33.Think of 15. Multiply it by 4, then add 5. What number do you end with?
- 34.I thought of a number, multiplied it by 2 and added 3. I got 9. What was my number?
- 35.Magic trick! Think of 6. Double it, add 6, halve it, then take away 6. What number do you get?
- 36.Magic trick! Think of 10. Double it, add 18, halve it, then take away 10. What number do you get?
- 37.Magic trick! Think of 11. Double it, add 12, halve it, then take away 11. What number do you get?
- 38.Think of 2. Multiply it by 2, then add 2. What number do you end with?
- 39.Think of 8. Multiply it by 5, then add 5. What number do you end with?
- 40.I thought of a number, multiplied it by 2 and added 3. I got 25. What was my number?
Answer key
- 3
- 28
- 73
- 6
- 10
- 14
- 5
- 5
- 9
- 3
- 3
- 9
- 8
- 5
- 14
- 11
- 5
- 2
- 23
- 4
- 15
- 7
- 3
- 4
- 2
- 10
- 6
- 21
- 43
- 48
- 5
- 66
- 65
- 3
- 3
- 9
- 6
- 6
- 45
- 11
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks