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 6. Double it, add 14, halve it, then take away 6. What number do you get?
- 2.I thought of a number, added 5 and then doubled it. I got 40. What was my number?
- 3.Think of 8. Multiply it by 4, then add 3. What number do you end with?
- 4.I thought of a number, multiplied it by 5 and added 6. I got 31. What was my number?
- 5.Think of 9. Multiply it by 5, then add 9. What number do you end with?
- 6.Magic trick! Think of 12. Double it, add 16, halve it, then take away 12. What number do you get?
- 7.I thought of a number, multiplied it by 5 and added 3. I got 33. What was my number?
- 8.Magic trick! Think of 6. Double it, add 18, halve it, then take away 6. What number do you get?
- 9.Think of 13. Multiply it by 5, then add 2. What number do you end with?
- 10.I thought of a number, added 2 and then doubled it. I got 36. What was my number?
- 11.I thought of a number, multiplied it by 3 and added 1. I got 37. What was my number?
- 12.I thought of a number, multiplied it by 4 and added 2. I got 38. What was my number?
- 13.I thought of a number, added 7 and then doubled it. I got 28. What was my number?
- 14.Magic trick! Think of 15. Double it, add 14, halve it, then take away 15. What number do you get?
- 15.I thought of a number, multiplied it by 3 and added 6. I got 18. What was my number?
- 16.I thought of a number, multiplied it by 3 and added 1. I got 13. What was my number?
- 17.Think of 4. Multiply it by 4, then add 6. What number do you end with?
- 18.I thought of a number, multiplied it by 4 and added 1. I got 9. What was my number?
- 19.Think of 6. Multiply it by 3, then add 7. What number do you end with?
- 20.Think of 4. Multiply it by 5, then add 2. What number do you end with?
- 21.Magic trick! Think of 9. Double it, add 18, halve it, then take away 9. What number do you get?
- 22.I thought of a number, added 3 and then doubled it. I got 28. What was my number?
- 23.Think of 12. Multiply it by 3, then add 3. What number do you end with?
- 24.Think of 12. Multiply it by 3, then add 9. What number do you end with?
- 25.Magic trick! Think of 15. Double it, add 8, halve it, then take away 15. What number do you get?
- 26.Magic trick! Think of 17. Double it, add 16, halve it, then take away 17. What number do you get?
- 27.I thought of a number, added 2 and then doubled it. I got 30. What was my number?
- 28.I thought of a number, added 1 and then doubled it. I got 34. What was my number?
- 29.Magic trick! Think of 11. Double it, add 6, halve it, then take away 11. What number do you get?
- 30.I thought of a number, added 1 and then doubled it. I got 38. What was my number?
- 31.Think of 8. Multiply it by 5, then add 7. What number do you end with?
- 32.Magic trick! Think of 17. Double it, add 10, halve it, then take away 17. What number do you get?
- 33.Magic trick! Think of 14. Double it, add 6, halve it, then take away 14. What number do you get?
- 34.Magic trick! Think of 8. Double it, add 6, halve it, then take away 8. What number do you get?
- 35.Think of 13. Multiply it by 3, then add 3. What number do you end with?
- 36.Magic trick! Think of 12. Double it, add 6, halve it, then take away 12. What number do you get?
- 37.I thought of a number, multiplied it by 4 and added 1. I got 13. What was my number?
- 38.I thought of a number, added 9 and then doubled it. I got 34. What was my number?
- 39.I thought of a number, multiplied it by 2 and added 1. I got 13. What was my number?
- 40.I thought of a number, multiplied it by 4 and added 2. I got 14. What was my number?
Answer key
- 7
- 15
- 35
- 5
- 54
- 8
- 6
- 9
- 67
- 16
- 12
- 9
- 7
- 7
- 4
- 4
- 22
- 2
- 25
- 22
- 9
- 11
- 39
- 45
- 4
- 8
- 13
- 16
- 3
- 18
- 47
- 5
- 3
- 3
- 42
- 3
- 3
- 8
- 6
- 3
Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks