← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 948 · 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. 1.5?27 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.3?58 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  3. 3.?782 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  4. 4.?03 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  5. 5.86?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  6. 6.42? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.70?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  8. 8.14?6 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  9. 9.Take 55 and take away the sum of its digits. What do you get?
  10. 10.17? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.?307 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  12. 12.?646 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  13. 13.Take 44 and take away the sum of its digits. What do you get?
  14. 14.Take 49 and take away the sum of its digits. What do you get?
  15. 15.Take 65 and take away the sum of its digits. What do you get?
  16. 16.?176 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  17. 17.4?70 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  18. 18.?329 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  19. 19.Take 68 and take away the sum of its digits. What do you get?
  20. 20.5?48 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.7?76 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  22. 22.Take 31 and take away the sum of its digits. What do you get?
  23. 23.Take 18 and take away the sum of its digits. What do you get?
  24. 24.?934 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.Take 93 and take away the sum of its digits. What do you get?
  26. 26.Take 89 and take away the sum of its digits. What do you get?
  27. 27.673? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.?05 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.Take 83 and take away the sum of its digits. What do you get?
  30. 30.?572 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.?241 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.230? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  33. 33.?350 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  34. 34.20?2 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  35. 35.415? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.4?84 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  37. 37.?002 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  38. 38.Take 29 and take away the sum of its digits. What do you get?
  39. 39.5?14 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  40. 40.7?27 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. 1
  4. 6
  5. 4
  6. 3
  7. 2
  8. 7
  9. 45
  10. 1
  11. 8
  12. 2
  13. 36
  14. 36
  15. 54
  16. 4
  17. 7
  18. 4
  19. 54
  20. 1
  21. 7
  22. 27
  23. 9
  24. 2
  25. 81
  26. 72
  27. 2
  28. 4
  29. 72
  30. 4
  31. 2
  32. 4
  33. 1
  34. 5
  35. 8
  36. 2
  37. 7
  38. 18
  39. 8
  40. 2

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