← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 207 · 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.?772 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.?978 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  3. 3.Take 30 and take away the sum of its digits. What do you get?
  4. 4.56?4 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  5. 5.62?2 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  6. 6.?105 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.7?59 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  8. 8.Take 97 and take away the sum of its digits. What do you get?
  9. 9.?860 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  10. 10.184? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.?466 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  12. 12.22?3 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  13. 13.65? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  14. 14.Take 46 and take away the sum of its digits. What do you get?
  15. 15.73?9 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  16. 16.270? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  17. 17.3?37 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  18. 18.10?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  19. 19.64?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  20. 20.?715 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.Take 99 and take away the sum of its digits. What do you get?
  22. 22.Take 26 and take away the sum of its digits. What do you get?
  23. 23.844? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.4?9 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.?73 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.?653 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  27. 27.58?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.2?65 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.Take 66 and take away the sum of its digits. What do you get?
  30. 30.8?31 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.27?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.332? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  33. 33.5?16 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  34. 34.Take 69 and take away the sum of its digits. What do you get?
  35. 35.?777 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.Take 22 and take away the sum of its digits. What do you get?
  37. 37.Take 89 and take away the sum of its digits. What do you get?
  38. 38.?155 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  39. 39.5?53 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  40. 40.740? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?

Answer key

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

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