← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 28 · 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 73 and take away the sum of its digits. What do you get?
  2. 2.5?2 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  3. 3.Take 65 and take away the sum of its digits. What do you get?
  4. 4.?394 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  5. 5.1?49 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  6. 6.4?24 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.Take 88 and take away the sum of its digits. What do you get?
  8. 8.?003 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  9. 9.Take 98 and take away the sum of its digits. What do you get?
  10. 10.?789 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.?056 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  12. 12.?845 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  13. 13.305? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  14. 14.?884 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  15. 15.480? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  16. 16.?560 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  17. 17.Take 35 and take away the sum of its digits. What do you get?
  18. 18.?282 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  19. 19.4?00 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  20. 20.1?68 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.1?55 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  22. 22.Take 75 and take away the sum of its digits. What do you get?
  23. 23.200? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.9?6 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.?803 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.880? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  27. 27.89?1 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.?407 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.Take 71 and take away the sum of its digits. What do you get?
  30. 30.?051 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.4?67 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.6?88 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  33. 33.Take 37 and take away the sum of its digits. What do you get?
  34. 34.Take 11 and take away the sum of its digits. What do you get?
  35. 35.Take 72 and take away the sum of its digits. What do you get?
  36. 36.15?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  37. 37.Take 62 and take away the sum of its digits. What do you get?
  38. 38.7?93 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  39. 39.131? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  40. 40.71?9 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?

Answer key

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

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