← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 645 · 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. 1.6?6 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.105? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  3. 3.?322 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  4. 4.Take 43 and take away the sum of its digits. What do you get?
  5. 5.?561 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  6. 6.?476 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.Take 52 and take away the sum of its digits. What do you get?
  8. 8.Take 47 and take away the sum of its digits. What do you get?
  9. 9.Take 95 and take away the sum of its digits. What do you get?
  10. 10.2?1 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.1?4 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  12. 12.Take 70 and take away the sum of its digits. What do you get?
  13. 13.6?14 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  14. 14.?452 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  15. 15.?22 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  16. 16.Take 13 and take away the sum of its digits. What do you get?
  17. 17.Take 87 and take away the sum of its digits. What do you get?
  18. 18.?043 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  19. 19.88?6 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  20. 20.1?61 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.Take 65 and take away the sum of its digits. What do you get?
  22. 22.Take 32 and take away the sum of its digits. What do you get?
  23. 23.?877 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.3?26 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.2?48 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.Take 58 and take away the sum of its digits. What do you get?
  27. 27.?620 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.Take 35 and take away the sum of its digits. What do you get?
  29. 29.414? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  30. 30.Take 74 and take away the sum of its digits. What do you get?
  31. 31.Take 17 and take away the sum of its digits. What do you get?
  32. 32.844? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  33. 33.?294 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  34. 34.?202 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  35. 35.5?59 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.Take 84 and take away the sum of its digits. What do you get?
  37. 37.Take 40 and take away the sum of its digits. What do you get?
  38. 38.?993 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  39. 39.Take 29 and take away the sum of its digits. What do you get?
  40. 40.?721 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. 3
  3. 2
  4. 36
  5. 6
  6. 1
  7. 45
  8. 36
  9. 81
  10. 6
  11. 4
  12. 63
  13. 7
  14. 7
  15. 5
  16. 9
  17. 72
  18. 2
  19. 5
  20. 1
  21. 54
  22. 27
  23. 5
  24. 7
  25. 4
  26. 45
  27. 1
  28. 27
  29. 9
  30. 63
  31. 9
  32. 2
  33. 3
  34. 5
  35. 8
  36. 72
  37. 36
  38. 6
  39. 18
  40. 8

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