← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 778 · 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. 1.532? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.Take 43 and take away the sum of its digits. What do you get?
  3. 3.Take 22 and take away the sum of its digits. What do you get?
  4. 4.8?7 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  5. 5.Take 97 and take away the sum of its digits. What do you get?
  6. 6.Take 90 and take away the sum of its digits. What do you get?
  7. 7.57?5 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  8. 8.Take 21 and take away the sum of its digits. What do you get?
  9. 9.Take 12 and take away the sum of its digits. What do you get?
  10. 10.?465 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.Take 34 and take away the sum of its digits. What do you get?
  12. 12.?55 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  13. 13.Take 67 and take away the sum of its digits. What do you get?
  14. 14.1?07 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  15. 15.169? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  16. 16.Take 41 and take away the sum of its digits. What do you get?
  17. 17.335? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  18. 18.?20 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  19. 19.4?53 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  20. 20.Take 50 and take away the sum of its digits. What do you get?
  21. 21.365? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  22. 22.Take 73 and take away the sum of its digits. What do you get?
  23. 23.39?3 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.462? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.62?5 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.?015 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  27. 27.Take 15 and take away the sum of its digits. What do you get?
  28. 28.34?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.Take 11 and take away the sum of its digits. What do you get?
  30. 30.?886 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.4?13 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.?428 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  33. 33.Take 19 and take away the sum of its digits. What do you get?
  34. 34.Take 33 and take away the sum of its digits. What do you get?
  35. 35.184? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.?148 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  37. 37.Take 80 and take away the sum of its digits. What do you get?
  38. 38.Take 58 and take away the sum of its digits. What do you get?
  39. 39.?736 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  40. 40.?093 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?

Answer key

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

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