← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 463 · 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. 1.2?39 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.?106 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  3. 3.Take 66 and take away the sum of its digits. What do you get?
  4. 4.1?52 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  5. 5.?120 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  6. 6.24?5 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.6?77 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  8. 8.?929 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  9. 9.57? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  10. 10.?191 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.Take 15 and take away the sum of its digits. What do you get?
  12. 12.Take 73 and take away the sum of its digits. What do you get?
  13. 13.Take 17 and take away the sum of its digits. What do you get?
  14. 14.Take 26 and take away the sum of its digits. What do you get?
  15. 15.16?6 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  16. 16.?353 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  17. 17.Take 16 and take away the sum of its digits. What do you get?
  18. 18.?664 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  19. 19.593? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  20. 20.740? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.6?06 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  22. 22.Take 71 and take away the sum of its digits. What do you get?
  23. 23.?889 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.?192 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.26?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.1?30 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  27. 27.?041 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.Take 13 and take away the sum of its digits. What do you get?
  29. 29.4?91 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  30. 30.?136 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.3?6 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.Take 46 and take away the sum of its digits. What do you get?
  33. 33.688? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  34. 34.?161 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  35. 35.Take 82 and take away the sum of its digits. What do you get?
  36. 36.Take 48 and take away the sum of its digits. What do you get?
  37. 37.6?20 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  38. 38.4?49 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  39. 39.Take 54 and take away the sum of its digits. What do you get?
  40. 40.75?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?

Answer key

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

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