← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 214 · 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.?604 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.?024 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  3. 3.6?62 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  4. 4.Take 38 and take away the sum of its digits. What do you get?
  5. 5.9?5 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  6. 6.Take 81 and take away the sum of its digits. What do you get?
  7. 7.294? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  8. 8.?250 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  9. 9.488? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  10. 10.89?9 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.Take 73 and take away the sum of its digits. What do you get?
  12. 12.745? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  13. 13.3?99 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  14. 14.53?1 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  15. 15.78?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  16. 16.?503 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. 18.169? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  19. 19.6?66 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  20. 20.?568 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.7?32 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  22. 22.51? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  23. 23.688? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.Take 51 and take away the sum of its digits. What do you get?
  25. 25.4?49 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.Take 23 and take away the sum of its digits. What do you get?
  27. 27.Take 91 and take away the sum of its digits. What do you get?
  28. 28.82?7 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.?057 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  30. 30.1?2 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.?71 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.?97 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  33. 33.Take 41 and take away the sum of its digits. What do you get?
  34. 34.Take 32 and take away the sum of its digits. What do you get?
  35. 35.68?7 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.?90 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  37. 37.Take 31 and take away the sum of its digits. What do you get?
  38. 38.4?91 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  39. 39.?643 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  40. 40.?112 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. 3
  3. 4
  4. 27
  5. 4
  6. 72
  7. 3
  8. 2
  9. 7
  10. 1
  11. 63
  12. 2
  13. 6
  14. 9
  15. 3
  16. 1
  17. 27
  18. 2
  19. 9
  20. 8
  21. 6
  22. 3
  23. 5
  24. 45
  25. 1
  26. 18
  27. 81
  28. 1
  29. 6
  30. 6
  31. 1
  32. 2
  33. 36
  34. 27
  35. 6
  36. 9
  37. 27
  38. 4
  39. 5
  40. 5

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