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 5 and added 1. I got 11. What was my number?
- 2.Think of 9. Multiply it by 3, then add 3. What number do you end with?
- 3.I thought of a number, added 7 and then doubled it. I got 22. What was my number?
- 4.I thought of a number, multiplied it by 2 and added 8. I got 16. What was my number?
- 5.Magic trick! Think of 14. Double it, add 16, halve it, then take away 14. What number do you get?
- 6.Magic trick! Think of 16. Double it, add 14, halve it, then take away 16. What number do you get?
- 7.Magic trick! Think of 15. Double it, add 4, halve it, then take away 15. What number do you get?
- 8.I thought of a number, multiplied it by 3 and added 8. I got 20. What was my number?
- 9.I thought of a number, multiplied it by 3 and added 1. I got 10. What was my number?
- 10.Magic trick! Think of 3. Double it, add 8, halve it, then take away 3. What number do you get?
- 11.Magic trick! Think of 9. Double it, add 12, halve it, then take away 9. What number do you get?
- 12.Think of 15. Multiply it by 2, then add 3. What number do you end with?
- 13.I thought of a number, added 7 and then doubled it. I got 44. What was my number?
- 14.Think of 6. Multiply it by 3, then add 5. What number do you end with?
- 15.I thought of a number, multiplied it by 3 and added 9. I got 54. What was my number?
- 16.I thought of a number, multiplied it by 2 and added 3. I got 27. What was my number?
- 17.I thought of a number, added 1 and then doubled it. I got 22. What was my number?
- 18.I thought of a number, multiplied it by 2 and added 7. I got 31. What was my number?
- 19.Magic trick! Think of 11. Double it, add 16, halve it, then take away 11. What number do you get?
- 20.Think of 2. Multiply it by 4, then add 1. What number do you end with?
- 21.Magic trick! Think of 2. Double it, add 12, halve it, then take away 2. What number do you get?
- 22.I thought of a number, multiplied it by 4 and added 3. I got 51. What was my number?
- 23.I thought of a number, multiplied it by 4 and added 9. I got 69. What was my number?
- 24.Magic trick! Think of 2. Double it, add 6, halve it, then take away 2. What number do you get?
- 25.I thought of a number, added 2 and then doubled it. I got 32. What was my number?
- 26.I thought of a number, multiplied it by 3 and added 5. I got 11. What was my number?
- 27.Think of 3. Multiply it by 4, then add 3. What number do you end with?
- 28.Magic trick! Think of 3. Double it, add 10, halve it, then take away 3. What number do you get?
- 29.Think of 5. Multiply it by 2, then add 2. What number do you end with?
- 30.I thought of a number, added 3 and then doubled it. I got 24. What was my number?
- 31.I thought of a number, multiplied it by 5 and added 1. I got 66. What was my number?
- 32.I thought of a number, multiplied it by 5 and added 5. I got 80. What was my number?
- 33.I thought of a number, multiplied it by 5 and added 9. I got 59. What was my number?
- 34.I thought of a number, multiplied it by 3 and added 6. I got 42. What was my number?
- 35.Think of 14. Multiply it by 3, then add 5. What number do you end with?
- 36.Magic trick! Think of 4. Double it, add 6, halve it, then take away 4. What number do you get?
- 37.Think of 9. Multiply it by 5, then add 4. What number do you end with?
- 38.Think of 2. Multiply it by 5, then add 1. What number do you end with?
- 39.Think of 6. Multiply it by 2, then add 8. What number do you end with?
- 40.I thought of a number, multiplied it by 2 and added 5. I got 21. What was my number?
Answer key
- 2
- 30
- 4
- 4
- 8
- 7
- 2
- 4
- 3
- 4
- 6
- 33
- 15
- 23
- 15
- 12
- 10
- 12
- 8
- 9
- 6
- 12
- 15
- 3
- 14
- 2
- 15
- 5
- 12
- 9
- 13
- 15
- 10
- 12
- 47
- 3
- 49
- 11
- 20
- 8
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks