← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 407 · 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 67 and take away the sum of its digits. What do you get?
  2. 2.7?08 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  3. 3.Take 69 and take away the sum of its digits. What do you get?
  4. 4.695? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  5. 5.Take 33 and take away the sum of its digits. What do you get?
  6. 6.409? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.9?4 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  8. 8.6?85 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  9. 9.Take 32 and take away the sum of its digits. What do you get?
  10. 10.Take 54 and take away the sum of its digits. What do you get?
  11. 11.?40 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  12. 12.87? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  13. 13.Take 99 and take away the sum of its digits. What do you get?
  14. 14.Take 18 and take away the sum of its digits. What do you get?
  15. 15.Take 85 and take away the sum of its digits. What do you get?
  16. 16.Take 53 and take away the sum of its digits. What do you get?
  17. 17.?88 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  18. 18.64?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  19. 19.Take 40 and take away the sum of its digits. What do you get?
  20. 20.48? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.666? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  22. 22.52?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  23. 23.1?84 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.5?09 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.856? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.?780 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  27. 27.22?6 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.4?20 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.?629 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  30. 30.?35 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.?867 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.?420 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  33. 33.33?7 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  34. 34.Take 59 and take away the sum of its digits. What do you get?
  35. 35.25? 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. 37.3?41 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  38. 38.Take 63 and take away the sum of its digits. What do you get?
  39. 39.479? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  40. 40.225? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?

Answer key

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

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