← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 444 · 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. 1.1?58 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.1?88 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  3. 3.?969 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  4. 4.Take 37 and take away the sum of its digits. What do you get?
  5. 5.Take 92 and take away the sum of its digits. What do you get?
  6. 6.Take 57 and take away the sum of its digits. What do you get?
  7. 7.Take 39 and take away the sum of its digits. What do you get?
  8. 8.?746 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  9. 9.?908 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  10. 10.?481 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.?013 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  12. 12.Take 66 and take away the sum of its digits. What do you get?
  13. 13.Take 68 and take away the sum of its digits. What do you get?
  14. 14.1?76 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  15. 15.40? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  16. 16.?179 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  17. 17.21?1 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  18. 18.?97 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  19. 19.?646 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  20. 20.7?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.Take 29 and take away the sum of its digits. What do you get?
  22. 22.Take 86 and take away the sum of its digits. What do you get?
  23. 23.8?33 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.Take 45 and take away the sum of its digits. What do you get?
  25. 25.176? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.?305 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  27. 27.42?9 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.8?95 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.Take 63 and take away the sum of its digits. What do you get?
  30. 30.Take 41 and take away the sum of its digits. What do you get?
  31. 31.Take 49 and take away the sum of its digits. What do you get?
  32. 32.Take 33 and take away the sum of its digits. What do you get?
  33. 33.?02 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  34. 34.Take 36 and take away the sum of its digits. What do you get?
  35. 35.2?08 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.51?9 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  37. 37.300? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  38. 38.8?23 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  39. 39.1?56 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  40. 40.2?89 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?

Answer key

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

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