← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 804 · 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. 1.6?70 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.Take 22 and take away the sum of its digits. What do you get?
  3. 3.8?09 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  4. 4.Take 81 and take away the sum of its digits. What do you get?
  5. 5.Take 44 and take away the sum of its digits. What do you get?
  6. 6.?68 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.?035 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  8. 8.71?6 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  9. 9.Take 57 and take away the sum of its digits. What do you get?
  10. 10.55?1 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.4?08 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  12. 12.?778 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  13. 13.Take 87 and take away the sum of its digits. What do you get?
  14. 14.15?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  15. 15.51?5 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  16. 16.82?5 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  17. 17.1?22 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  18. 18.?35 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  19. 19.Take 84 and take away the sum of its digits. What do you get?
  20. 20.Take 11 and take away the sum of its digits. What do you get?
  21. 21.382? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  22. 22.?794 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  23. 23.?359 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.36?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.?75 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.4?15 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  27. 27.17?4 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.Take 88 and take away the sum of its digits. What do you get?
  29. 29.88?7 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  30. 30.70?7 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.8?97 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.?907 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  33. 33.?46 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  34. 34.?955 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  35. 35.46?7 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.?804 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  37. 37.?749 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  38. 38.?460 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  39. 39.390? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  40. 40.Take 19 and take away the sum of its digits. What do you get?

Answer key

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

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