← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 562 · 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 86 and take away the sum of its digits. What do you get?
  2. 2.Take 12 and take away the sum of its digits. What do you get?
  3. 3.?075 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  4. 4.28?6 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  5. 5.?694 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  6. 6.?016 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.772? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  8. 8.39?6 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  9. 9.?753 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  10. 10.66?3 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.8?32 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  12. 12.Take 19 and take away the sum of its digits. What do you get?
  13. 13.Take 87 and take away the sum of its digits. What do you get?
  14. 14.Take 21 and take away the sum of its digits. What do you get?
  15. 15.88?5 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  16. 16.?802 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  17. 17.Take 89 and take away the sum of its digits. What do you get?
  18. 18.274? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  19. 19.4?28 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  20. 20.?779 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.31? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  22. 22.Take 71 and take away the sum of its digits. What do you get?
  23. 23.?179 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.27?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.6?37 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.?869 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  27. 27.3?99 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.?856 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.?88 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  30. 30.Take 60 and take away the sum of its digits. What do you get?
  31. 31.?545 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.Take 72 and take away the sum of its digits. What do you get?
  33. 33.44?9 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  34. 34.27?6 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  35. 35.15?2 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.37?9 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  37. 37.30?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  38. 38.6?23 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  39. 39.Take 58 and take away the sum of its digits. What do you get?
  40. 40.?552 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?

Answer key

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

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