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Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 269 · 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. 1.7?3 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.?366 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  3. 3.59?4 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  4. 4.Take 97 and take away the sum of its digits. What do you get?
  5. 5.Take 16 and take away the sum of its digits. What do you get?
  6. 6.Take 12 and take away the sum of its digits. What do you get?
  7. 7.6?9 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  8. 8.66?6 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  9. 9.?062 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  10. 10.7?00 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.9?9 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  12. 12.598? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  13. 13.757? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  14. 14.?924 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  15. 15.Take 85 and take away the sum of its digits. What do you get?
  16. 16.Take 25 and take away the sum of its digits. What do you get?
  17. 17.Take 68 and take away the sum of its digits. What do you get?
  18. 18.Take 60 and take away the sum of its digits. What do you get?
  19. 19.850? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  20. 20.270? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.Take 34 and take away the sum of its digits. What do you get?
  22. 22.?883 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  23. 23.?408 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.212? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.Take 39 and take away the sum of its digits. What do you get?
  26. 26.5?87 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  27. 27.?555 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.39?4 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.1?48 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  30. 30.?863 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.1?00 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.67?9 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  33. 33.5?90 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  34. 34.?989 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  35. 35.?712 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.59?9 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  37. 37.?518 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  38. 38.?520 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  39. 39.?002 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  40. 40.841? 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. 9
  4. 81
  5. 9
  6. 9
  7. 3
  8. 9
  9. 1
  10. 2
  11. 9
  12. 5
  13. 8
  14. 3
  15. 72
  16. 18
  17. 54
  18. 54
  19. 5
  20. 9
  21. 27
  22. 8
  23. 6
  24. 4
  25. 27
  26. 7
  27. 3
  28. 2
  29. 5
  30. 1
  31. 8
  32. 5
  33. 4
  34. 1
  35. 8
  36. 4
  37. 4
  38. 2
  39. 7
  40. 5

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