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.Think of 13. Multiply it by 2, then add 1. What number do you end with?
- 2.I thought of a number, added 5 and then doubled it. I got 28. What was my number?
- 3.Magic trick! Think of 14. Double it, add 12, halve it, then take away 14. What number do you get?
- 4.Magic trick! Think of 16. Double it, add 4, halve it, then take away 16. What number do you get?
- 5.Think of 9. Multiply it by 5, then add 3. What number do you end with?
- 6.I thought of a number, multiplied it by 2 and added 5. I got 33. What was my number?
- 7.Magic trick! Think of 12. Double it, add 16, halve it, then take away 12. What number do you get?
- 8.Think of 14. Multiply it by 3, then add 7. What number do you end with?
- 9.Think of 6. Multiply it by 2, then add 6. What number do you end with?
- 10.Think of 4. Multiply it by 5, then add 3. What number do you end with?
- 11.Magic trick! Think of 13. Double it, add 10, halve it, then take away 13. What number do you get?
- 12.I thought of a number, multiplied it by 4 and added 2. I got 42. What was my number?
- 13.I thought of a number, multiplied it by 3 and added 7. I got 46. What was my number?
- 14.Think of 10. Multiply it by 3, then add 5. What number do you end with?
- 15.I thought of a number, multiplied it by 5 and added 1. I got 26. What was my number?
- 16.Magic trick! Think of 5. Double it, add 4, halve it, then take away 5. What number do you get?
- 17.Think of 5. Multiply it by 2, then add 7. What number do you end with?
- 18.I thought of a number, added 1 and then doubled it. I got 26. What was my number?
- 19.Magic trick! Think of 16. Double it, add 18, halve it, then take away 16. What number do you get?
- 20.I thought of a number, added 7 and then doubled it. I got 50. What was my number?
- 21.Think of 2. Multiply it by 2, then add 9. What number do you end with?
- 22.Magic trick! Think of 9. Double it, add 14, halve it, then take away 9. What number do you get?
- 23.Magic trick! Think of 2. Double it, add 6, halve it, then take away 2. What number do you get?
- 24.I thought of a number, added 6 and then doubled it. I got 20. What was my number?
- 25.I thought of a number, added 7 and then doubled it. I got 34. What was my number?
- 26.Think of 10. Multiply it by 5, then add 2. What number do you end with?
- 27.I thought of a number, multiplied it by 5 and added 4. I got 34. What was my number?
- 28.I thought of a number, added 8 and then doubled it. I got 40. What was my number?
- 29.Think of 6. Multiply it by 4, then add 6. What number do you end with?
- 30.Think of 11. Multiply it by 4, then add 2. What number do you end with?
- 31.I thought of a number, multiplied it by 4 and added 3. I got 31. What was my number?
- 32.Magic trick! Think of 10. Double it, add 8, halve it, then take away 10. What number do you get?
- 33.I thought of a number, added 8 and then doubled it. I got 42. What was my number?
- 34.Think of 2. Multiply it by 4, then add 4. What number do you end with?
- 35.Think of 14. Multiply it by 4, then add 7. What number do you end with?
- 36.Magic trick! Think of 6. Double it, add 16, halve it, then take away 6. What number do you get?
- 37.I thought of a number, added 2 and then doubled it. I got 40. What was my number?
- 38.Magic trick! Think of 19. Double it, add 18, halve it, then take away 19. What number do you get?
- 39.I thought of a number, multiplied it by 3 and added 1. I got 25. What was my number?
- 40.Think of 10. Multiply it by 2, then add 1. What number do you end with?
Answer key
- 27
- 9
- 6
- 2
- 48
- 14
- 8
- 49
- 18
- 23
- 5
- 10
- 13
- 35
- 5
- 2
- 17
- 12
- 9
- 18
- 13
- 7
- 3
- 4
- 10
- 52
- 6
- 12
- 30
- 46
- 7
- 4
- 13
- 12
- 63
- 8
- 18
- 9
- 8
- 21
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks