← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 474 · 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. 1.127? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.380? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  3. 3.356? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  4. 4.3?47 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  5. 5.177? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  6. 6.20?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.Take 25 and take away the sum of its digits. What do you get?
  8. 8.1?89 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  9. 9.2?63 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  10. 10.Take 93 and take away the sum of its digits. What do you get?
  11. 11.Take 88 and take away the sum of its digits. What do you get?
  12. 12.58?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  13. 13.Take 72 and take away the sum of its digits. What do you get?
  14. 14.Take 11 and take away the sum of its digits. What do you get?
  15. 15.?30 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  16. 16.36?2 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.Take 76 and take away the sum of its digits. What do you get?
  19. 19.Take 85 and take away the sum of its digits. What do you get?
  20. 20.1?83 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.41?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  22. 22.1?44 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  23. 23.287? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.Take 77 and take away the sum of its digits. What do you get?
  25. 25.234? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.Take 33 and take away the sum of its digits. What do you get?
  27. 27.8?58 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.7?82 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.4?66 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  30. 30.Take 81 and take away the sum of its digits. What do you get?
  31. 31.Take 23 and take away the sum of its digits. What do you get?
  32. 32.89?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  33. 33.34? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  34. 34.Take 17 and take away the sum of its digits. What do you get?
  35. 35.?389 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.71? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  37. 37.Take 30 and take away the sum of its digits. What do you get?
  38. 38.Take 24 and take away the sum of its digits. What do you get?
  39. 39.5?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  40. 40.Take 35 and take away the sum of its digits. What do you get?

Answer key

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

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