← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 205 · 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.Take 90 and take away the sum of its digits. What do you get?
  2. 2.14?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  3. 3.?994 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  4. 4.6?32 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  5. 5.73?2 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  6. 6.12?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.Take 49 and take away the sum of its digits. What do you get?
  8. 8.Take 33 and take away the sum of its digits. What do you get?
  9. 9.41?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  10. 10.?330 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.84?2 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  12. 12.?428 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  13. 13.3?45 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  14. 14.?258 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  15. 15.Take 88 and take away the sum of its digits. What do you get?
  16. 16.566? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  17. 17.363? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  18. 18.Take 11 and take away the sum of its digits. What do you get?
  19. 19.5?47 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  20. 20.64?4 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.?262 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  22. 22.Take 69 and take away the sum of its digits. What do you get?
  23. 23.?858 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.881? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.185? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.Take 63 and take away the sum of its digits. What do you get?
  27. 27.?114 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.Take 95 and take away the sum of its digits. What do you get?
  29. 29.Take 62 and take away the sum of its digits. What do you get?
  30. 30.?002 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.?898 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.?943 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  33. 33.Take 43 and take away the sum of its digits. What do you get?
  34. 34.785? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  35. 35.189? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.Take 97 and take away the sum of its digits. What do you get?
  37. 37.Take 72 and take away the sum of its digits. What do you get?
  38. 38.Take 53 and take away the sum of its digits. What do you get?
  39. 39.Take 93 and take away the sum of its digits. What do you get?
  40. 40.Take 77 and take away the sum of its digits. What do you get?

Answer key

  1. 81
  2. 5
  3. 5
  4. 7
  5. 6
  6. 7
  7. 36
  8. 27
  9. 4
  10. 3
  11. 4
  12. 4
  13. 6
  14. 3
  15. 72
  16. 1
  17. 6
  18. 9
  19. 2
  20. 4
  21. 8
  22. 54
  23. 6
  24. 1
  25. 4
  26. 54
  27. 3
  28. 81
  29. 54
  30. 7
  31. 2
  32. 2
  33. 36
  34. 7
  35. 9
  36. 81
  37. 63
  38. 45
  39. 81
  40. 63

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