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Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 356 · 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 95 and take away the sum of its digits. What do you get?
  2. 2.?049 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  3. 3.231? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  4. 4.64?7 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  5. 5.50?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  6. 6.?933 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.67?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  8. 8.239? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  9. 9.Take 42 and take away the sum of its digits. What do you get?
  10. 10.?483 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.Take 35 and take away the sum of its digits. What do you get?
  12. 12.Take 40 and take away the sum of its digits. What do you get?
  13. 13.14?2 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  14. 14.?703 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  15. 15.?004 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  16. 16.57?2 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  17. 17.41?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  18. 18.Take 83 and take away the sum of its digits. What do you get?
  19. 19.Take 62 and take away the sum of its digits. What do you get?
  20. 20.?890 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.?23 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  22. 22.877? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  23. 23.292? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.?052 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.816? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.?717 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  27. 27.7?22 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.?039 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.Take 30 and take away the sum of its digits. What do you get?
  30. 30.80?9 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.225? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.?24 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  33. 33.709? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  34. 34.777? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  35. 35.?60 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.Take 52 and take away the sum of its digits. What do you get?
  37. 37.Take 98 and take away the sum of its digits. What do you get?
  38. 38.?646 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  39. 39.671? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  40. 40.?358 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?

Answer key

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

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