← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 621 · 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. 1.3?84 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.?037 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  3. 3.16?1 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  4. 4.173? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  5. 5.38?7 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  6. 6.Take 23 and take away the sum of its digits. What do you get?
  7. 7.Take 75 and take away the sum of its digits. What do you get?
  8. 8.303? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  9. 9.7?14 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  10. 10.1?23 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.2?21 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  12. 12.?088 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  13. 13.Take 82 and take away the sum of its digits. What do you get?
  14. 14.25?3 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  15. 15.Take 99 and take away the sum of its digits. What do you get?
  16. 16.35?2 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  17. 17.Take 15 and take away the sum of its digits. What do you get?
  18. 18.Take 45 and take away the sum of its digits. What do you get?
  19. 19.Take 16 and take away the sum of its digits. What do you get?
  20. 20.89?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.?93 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  22. 22.849? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  23. 23.Take 13 and take away the sum of its digits. What do you get?
  24. 24.256? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.?635 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.Take 12 and take away the sum of its digits. What do you get?
  27. 27.Take 43 and take away the sum of its digits. What do you get?
  28. 28.Take 83 and take away the sum of its digits. What do you get?
  29. 29.Take 69 and take away the sum of its digits. What do you get?
  30. 30.Take 56 and take away the sum of its digits. What do you get?
  31. 31.6?3 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.Take 42 and take away the sum of its digits. What do you get?
  33. 33.2?58 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  34. 34.1?66 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  35. 35.1?6 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.?361 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  37. 37.7?20 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  38. 38.5?25 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  39. 39.78?6 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  40. 40.Take 77 and take away the sum of its digits. What do you get?

Answer key

  1. 3
  2. 8
  3. 1
  4. 7
  5. 9
  6. 18
  7. 63
  8. 3
  9. 6
  10. 3
  11. 4
  12. 2
  13. 72
  14. 8
  15. 81
  16. 8
  17. 9
  18. 36
  19. 9
  20. 1
  21. 6
  22. 6
  23. 9
  24. 5
  25. 4
  26. 9
  27. 36
  28. 72
  29. 54
  30. 45
  31. 9
  32. 36
  33. 3
  34. 5
  35. 2
  36. 8
  37. 9
  38. 6
  39. 6
  40. 63

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