← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 852 · 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 38 and take away the sum of its digits. What do you get?
  2. 2.25? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  3. 3.Take 45 and take away the sum of its digits. What do you get?
  4. 4.7?29 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  5. 5.225? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  6. 6.79?5 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.?430 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  8. 8.Take 72 and take away the sum of its digits. What do you get?
  9. 9.Take 27 and take away the sum of its digits. What do you get?
  10. 10.80?3 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.392? 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. 13.33?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  14. 14.Take 21 and take away the sum of its digits. What do you get?
  15. 15.?201 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  16. 16.?31 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  17. 17.6?88 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  18. 18.?382 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  19. 19.2?11 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  20. 20.?466 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.Take 14 and take away the sum of its digits. What do you get?
  22. 22.490? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  23. 23.Take 60 and take away the sum of its digits. What do you get?
  24. 24.26?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.17?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.6?56 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  27. 27.2?43 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.883? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.?218 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  30. 30.Take 95 and take away the sum of its digits. What do you get?
  31. 31.Take 52 and take away the sum of its digits. What do you get?
  32. 32.660? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  33. 33.834? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  34. 34.Take 63 and take away the sum of its digits. What do you get?
  35. 35.784? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.781? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  37. 37.9?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  38. 38.Take 19 and take away the sum of its digits. What do you get?
  39. 39.250? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  40. 40.17?1 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?

Answer key

  1. 27
  2. 2
  3. 36
  4. 9
  5. 9
  6. 6
  7. 2
  8. 63
  9. 18
  10. 7
  11. 4
  12. 5
  13. 3
  14. 18
  15. 6
  16. 5
  17. 5
  18. 5
  19. 5
  20. 2
  21. 9
  22. 5
  23. 54
  24. 2
  25. 2
  26. 1
  27. 9
  28. 8
  29. 7
  30. 81
  31. 45
  32. 6
  33. 3
  34. 54
  35. 8
  36. 2
  37. 9
  38. 9
  39. 2
  40. 9

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