← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 278 · 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. 1.1?92 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.?116 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.?439 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  5. 5.Take 57 and take away the sum of its digits. What do you get?
  6. 6.1?17 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.Take 48 and take away the sum of its digits. What do you get?
  8. 8.7?74 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  9. 9.Take 79 and take away the sum of its digits. What do you get?
  10. 10.Take 51 and take away the sum of its digits. What do you get?
  11. 11.1?02 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  12. 12.?394 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  13. 13.34?7 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  14. 14.?632 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  15. 15.Take 21 and take away the sum of its digits. What do you get?
  16. 16.7?58 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  17. 17.?83 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  18. 18.2?57 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  19. 19.Take 37 and take away the sum of its digits. What do you get?
  20. 20.1?24 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.79?6 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  22. 22.424? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  23. 23.Take 24 and take away the sum of its digits. What do you get?
  24. 24.?220 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.Take 16 and take away the sum of its digits. What do you get?
  26. 26.?935 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  27. 27.45?5 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.817? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.396? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  30. 30.32? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.?865 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.60? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  33. 33.27?7 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  34. 34.Take 17 and take away the sum of its digits. What do you get?
  35. 35.?236 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.410? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  37. 37.Take 99 and take away the sum of its digits. What do you get?
  38. 38.Take 93 and take away the sum of its digits. What do you get?
  39. 39.?384 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  40. 40.?148 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?

Answer key

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

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