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 2 and added 2. I got 18. What was my number?
- 2.Think of 2. Multiply it by 4, then add 2. What number do you end with?
- 3.Magic trick! Think of 10. Double it, add 14, halve it, then take away 10. What number do you get?
- 4.Think of 13. Multiply it by 4, then add 2. What number do you end with?
- 5.I thought of a number, multiplied it by 4 and added 6. I got 38. What was my number?
- 6.Think of 9. Multiply it by 5, then add 2. What number do you end with?
- 7.I thought of a number, added 4 and then doubled it. I got 30. What was my number?
- 8.Think of 2. Multiply it by 4, then add 4. What number do you end with?
- 9.Think of 10. Multiply it by 2, then add 8. What number do you end with?
- 10.Magic trick! Think of 5. Double it, add 12, halve it, then take away 5. What number do you get?
- 11.I thought of a number, added 3 and then doubled it. I got 18. What was my number?
- 12.I thought of a number, multiplied it by 5 and added 7. I got 67. What was my number?
- 13.Magic trick! Think of 9. Double it, add 6, halve it, then take away 9. What number do you get?
- 14.I thought of a number, added 7 and then doubled it. I got 32. What was my number?
- 15.I thought of a number, added 9 and then doubled it. I got 58. What was my number?
- 16.I thought of a number, multiplied it by 5 and added 5. I got 25. What was my number?
- 17.I thought of a number, added 8 and then doubled it. I got 54. What was my number?
- 18.I thought of a number, multiplied it by 4 and added 3. I got 31. What was my number?
- 19.I thought of a number, multiplied it by 3 and added 9. I got 42. What was my number?
- 20.I thought of a number, added 2 and then doubled it. I got 34. What was my number?
- 21.I thought of a number, multiplied it by 5 and added 8. I got 33. What was my number?
- 22.Magic trick! Think of 10. Double it, add 8, halve it, then take away 10. What number do you get?
- 23.Magic trick! Think of 12. Double it, add 6, halve it, then take away 12. What number do you get?
- 24.Think of 14. Multiply it by 5, then add 8. What number do you end with?
- 25.Magic trick! Think of 20. Double it, add 12, halve it, then take away 20. What number do you get?
- 26.I thought of a number, added 6 and then doubled it. I got 36. What was my number?
- 27.Think of 9. Multiply it by 5, then add 7. What number do you end with?
- 28.I thought of a number, added 5 and then doubled it. I got 28. What was my number?
- 29.Think of 11. Multiply it by 5, then add 9. What number do you end with?
- 30.Magic trick! Think of 5. Double it, add 18, halve it, then take away 5. What number do you get?
- 31.Think of 3. Multiply it by 5, then add 5. What number do you end with?
- 32.Magic trick! Think of 11. Double it, add 10, halve it, then take away 11. What number do you get?
- 33.Think of 8. Multiply it by 3, then add 2. What number do you end with?
- 34.I thought of a number, added 1 and then doubled it. I got 18. What was my number?
- 35.Magic trick! Think of 8. Double it, add 18, halve it, then take away 8. What number do you get?
- 36.Magic trick! Think of 5. Double it, add 8, halve it, then take away 5. What number do you get?
- 37.Magic trick! Think of 5. Double it, add 16, halve it, then take away 5. What number do you get?
- 38.I thought of a number, added 6 and then doubled it. I got 30. What was my number?
- 39.I thought of a number, multiplied it by 4 and added 7. I got 31. What was my number?
- 40.Magic trick! Think of 11. Double it, add 4, halve it, then take away 11. What number do you get?
Answer key
- 8
- 10
- 7
- 54
- 8
- 47
- 11
- 12
- 28
- 6
- 6
- 12
- 3
- 9
- 20
- 4
- 19
- 7
- 11
- 15
- 5
- 4
- 3
- 78
- 6
- 12
- 52
- 9
- 64
- 9
- 20
- 5
- 26
- 8
- 9
- 4
- 8
- 9
- 6
- 2
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks