← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 503 · 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. 1.37?4 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.8?80 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  3. 3.?313 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  4. 4.Take 82 and take away the sum of its digits. What do you get?
  5. 5.Take 20 and take away the sum of its digits. What do you get?
  6. 6.Take 97 and take away the sum of its digits. What do you get?
  7. 7.Take 53 and take away the sum of its digits. What do you get?
  8. 8.Take 87 and take away the sum of its digits. What do you get?
  9. 9.Take 42 and take away the sum of its digits. What do you get?
  10. 10.Take 13 and take away the sum of its digits. What do you get?
  11. 11.?219 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  12. 12.47?6 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  13. 13.Take 30 and take away the sum of its digits. What do you get?
  14. 14.Take 48 and take away the sum of its digits. What do you get?
  15. 15.Take 81 and take away the sum of its digits. What do you get?
  16. 16.?694 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  17. 17.38? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  18. 18.4?03 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  19. 19.Take 94 and take away the sum of its digits. What do you get?
  20. 20.Take 44 and take away the sum of its digits. What do you get?
  21. 21.Take 16 and take away the sum of its digits. What do you get?
  22. 22.?458 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  23. 23.58?9 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.?578 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.21?3 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.Take 78 and take away the sum of its digits. What do you get?
  27. 27.13?1 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.?466 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.Take 89 and take away the sum of its digits. What do you get?
  30. 30.61?3 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.Take 12 and take away the sum of its digits. What do you get?
  32. 32.Take 49 and take away the sum of its digits. What do you get?
  33. 33.?292 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  34. 34.Take 41 and take away the sum of its digits. What do you get?
  35. 35.Take 76 and take away the sum of its digits. What do you get?
  36. 36.82?2 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  37. 37.?059 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  38. 38.36?2 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  39. 39.802? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  40. 40.66?2 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. 2
  3. 2
  4. 72
  5. 18
  6. 81
  7. 45
  8. 72
  9. 36
  10. 9
  11. 6
  12. 1
  13. 27
  14. 36
  15. 72
  16. 8
  17. 7
  18. 2
  19. 81
  20. 36
  21. 9
  22. 1
  23. 5
  24. 7
  25. 3
  26. 63
  27. 4
  28. 2
  29. 72
  30. 8
  31. 9
  32. 36
  33. 5
  34. 36
  35. 63
  36. 6
  37. 4
  38. 7
  39. 8
  40. 4

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