← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 593 · 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. 1.514? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.53?7 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  3. 3.?878 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  4. 4.404? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  5. 5.Take 31 and take away the sum of its digits. What do you get?
  6. 6.19?7 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.6?00 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  8. 8.?265 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  9. 9.?509 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  10. 10.518? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.165? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  12. 12.Take 57 and take away the sum of its digits. What do you get?
  13. 13.137? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  14. 14.49?5 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  15. 15.8?34 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  16. 16.Take 34 and take away the sum of its digits. What do you get?
  17. 17.4?63 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  18. 18.38?2 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  19. 19.1?28 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  20. 20.?727 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.Take 93 and take away the sum of its digits. What do you get?
  22. 22.496? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  23. 23.Take 47 and take away the sum of its digits. What do you get?
  24. 24.17?2 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.?71 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.Take 74 and take away the sum of its digits. What do you get?
  27. 27.3?70 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.?596 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.777? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  30. 30.41?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.Take 44 and take away the sum of its digits. What do you get?
  32. 32.682? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  33. 33.Take 30 and take away the sum of its digits. What do you get?
  34. 34.1?18 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  35. 35.?826 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.Take 56 and take away the sum of its digits. What do you get?
  37. 37.Take 81 and take away the sum of its digits. What do you get?
  38. 38.1?96 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.?353 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. 1
  5. 27
  6. 1
  7. 3
  8. 5
  9. 4
  10. 4
  11. 6
  12. 45
  13. 7
  14. 9
  15. 3
  16. 27
  17. 5
  18. 5
  19. 7
  20. 2
  21. 81
  22. 8
  23. 36
  24. 8
  25. 1
  26. 63
  27. 8
  28. 7
  29. 6
  30. 5
  31. 36
  32. 2
  33. 27
  34. 8
  35. 2
  36. 45
  37. 72
  38. 2
  39. 45
  40. 7

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