← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 732 · 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.?130 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.?888 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  3. 3.89?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  4. 4.643? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  5. 5.?690 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  6. 6.16?3 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.?383 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  8. 8.Take 95 and take away the sum of its digits. What do you get?
  9. 9.77?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  10. 10.8?01 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.?633 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  12. 12.64?9 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  13. 13.?001 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  14. 14.1?67 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  15. 15.148? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  16. 16.80?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  17. 17.Take 36 and take away the sum of its digits. What do you get?
  18. 18.39?1 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  19. 19.?020 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  20. 20.Take 35 and take away the sum of its digits. What do you get?
  21. 21.?99 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  22. 22.?86 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  23. 23.?034 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.?460 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.Take 75 and take away the sum of its digits. What do you get?
  26. 26.476? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  27. 27.Take 48 and take away the sum of its digits. What do you get?
  28. 28.79?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.1?05 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  30. 30.3?74 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.18?9 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.Take 13 and take away the sum of its digits. What do you get?
  33. 33.5?07 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  34. 34.?664 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  35. 35.867? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.Take 38 and take away the sum of its digits. What do you get?
  37. 37.Take 70 and take away the sum of its digits. What do you get?
  38. 38.46?3 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. 40.11?8 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. 3
  3. 2
  4. 5
  5. 3
  6. 8
  7. 4
  8. 81
  9. 5
  10. 9
  11. 6
  12. 8
  13. 8
  14. 4
  15. 5
  16. 2
  17. 27
  18. 5
  19. 7
  20. 27
  21. 9
  22. 4
  23. 2
  24. 8
  25. 63
  26. 1
  27. 36
  28. 3
  29. 3
  30. 4
  31. 9
  32. 9
  33. 6
  34. 2
  35. 6
  36. 27
  37. 63
  38. 5
  39. 45
  40. 8

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