← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 955 · 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. 1.4?63 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.Take 29 and take away the sum of its digits. What do you get?
  3. 3.Take 84 and take away the sum of its digits. What do you get?
  4. 4.150? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  5. 5.Take 61 and take away the sum of its digits. What do you get?
  6. 6.?863 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.Take 32 and take away the sum of its digits. What do you get?
  8. 8.Take 13 and take away the sum of its digits. What do you get?
  9. 9.?196 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  10. 10.369? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.27?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  12. 12.Take 65 and take away the sum of its digits. What do you get?
  13. 13.Take 15 and take away the sum of its digits. What do you get?
  14. 14.?762 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  15. 15.801? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  16. 16.Take 37 and take away the sum of its digits. What do you get?
  17. 17.?824 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  18. 18.3?2 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  19. 19.14?4 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  20. 20.1?56 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.2?76 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  22. 22.4?27 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  23. 23.736? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.70?7 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.8?80 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.68?4 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  27. 27.Take 99 and take away the sum of its digits. What do you get?
  28. 28.57?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.?07 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  30. 30.800? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.16?4 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.Take 26 and take away the sum of its digits. What do you get?
  34. 34.Take 17 and take away the sum of its digits. What do you get?
  35. 35.61?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.9?4 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  37. 37.Take 56 and take away the sum of its digits. What do you get?
  38. 38.82? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  39. 39.47?4 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  40. 40.522? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?

Answer key

  1. 5
  2. 18
  3. 72
  4. 3
  5. 54
  6. 1
  7. 27
  8. 9
  9. 2
  10. 9
  11. 9
  12. 54
  13. 9
  14. 3
  15. 9
  16. 27
  17. 4
  18. 4
  19. 9
  20. 6
  21. 3
  22. 5
  23. 2
  24. 4
  25. 2
  26. 9
  27. 81
  28. 7
  29. 2
  30. 1
  31. 7
  32. 72
  33. 18
  34. 9
  35. 2
  36. 5
  37. 45
  38. 8
  39. 3
  40. 9

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