← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 795 · 40 questions
TalentJR

The trick (Digits add to the 9 table): Add the digits you can see. Find the next number in the 9 table (9, 18, 27 …) above that total. The hidden digit is the difference. (Any number minus its digit sum is in the 9 table too.)

NameDateTime takenScore ___ / 40
  1. 1.457? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.?865 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  3. 3.Take 79 and take away the sum of its digits. What do you get?
  4. 4.3?87 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  5. 5.?588 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  6. 6.79?1 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.67?3 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  8. 8.?066 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  9. 9.Take 19 and take away the sum of its digits. What do you get?
  10. 10.?163 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.2?55 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  12. 12.29?7 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  13. 13.Take 22 and take away the sum of its digits. What do you get?
  14. 14.Take 16 and take away the sum of its digits. What do you get?
  15. 15.3?19 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  16. 16.211? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  17. 17.1?51 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  18. 18.Take 62 and take away the sum of its digits. What do you get?
  19. 19.?80 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  20. 20.6?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.Take 29 and take away the sum of its digits. What do you get?
  22. 22.?283 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  23. 23.Take 39 and take away the sum of its digits. What do you get?
  24. 24.?823 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.Take 11 and take away the sum of its digits. What do you get?
  26. 26.1?05 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  27. 27.583? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.?431 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.210? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  30. 30.?690 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.?556 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.Take 87 and take away the sum of its digits. What do you get?
  33. 33.8?38 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  34. 34.887? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  35. 35.52?4 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.6?3 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  37. 37.Take 26 and take away the sum of its digits. What do you get?
  38. 38.?034 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  39. 39.18?5 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  40. 40.Take 53 and take away the sum of its digits. What do you get?

Answer key

  1. 2
  2. 8
  3. 63
  4. 9
  5. 6
  6. 1
  7. 2
  8. 6
  9. 9
  10. 8
  11. 6
  12. 9
  13. 18
  14. 9
  15. 5
  16. 5
  17. 2
  18. 54
  19. 1
  20. 4
  21. 18
  22. 5
  23. 27
  24. 5
  25. 9
  26. 3
  27. 2
  28. 1
  29. 6
  30. 3
  31. 2
  32. 72
  33. 8
  34. 4
  35. 7
  36. 9
  37. 18
  38. 2
  39. 4
  40. 45

Free maths tricks lessons, practice and worksheets at talentjr.in/maths-tricks