← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 545 · 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.?280 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.Take 27 and take away the sum of its digits. What do you get?
  3. 3.1?09 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  4. 4.467? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  5. 5.3?06 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  6. 6.2?35 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.Take 22 and take away the sum of its digits. What do you get?
  8. 8.40?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  9. 9.56?6 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  10. 10.247? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.Take 99 and take away the sum of its digits. What do you get?
  12. 12.470? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  13. 13.?580 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  14. 14.?871 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  15. 15.Take 85 and take away the sum of its digits. What do you get?
  16. 16.?46 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  17. 17.68?2 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  18. 18.?266 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  19. 19.?255 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  20. 20.?301 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.?498 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  22. 22.Take 15 and take away the sum of its digits. What do you get?
  23. 23.3?67 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.16?2 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.38? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.88?7 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  27. 27.201? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.776? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.?687 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  30. 30.?264 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.610? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.?01 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  33. 33.387? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  34. 34.144? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  35. 35.Take 37 and take away the sum of its digits. What do you get?
  36. 36.52?1 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  37. 37.Take 60 and take away the sum of its digits. What do you get?
  38. 38.7?42 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  39. 39.153? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  40. 40.?075 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?

Answer key

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

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