← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 769 · 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.?463 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.Take 64 and take away the sum of its digits. What do you get?
  3. 3.?230 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  4. 4.Take 55 and take away the sum of its digits. What do you get?
  5. 5.Take 44 and take away the sum of its digits. What do you get?
  6. 6.Take 73 and take away the sum of its digits. What do you get?
  7. 7.41?3 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  8. 8.Take 72 and take away the sum of its digits. What do you get?
  9. 9.592? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  10. 10.83?6 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.5?54 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  12. 12.?768 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  13. 13.647? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  14. 14.Take 95 and take away the sum of its digits. What do you get?
  15. 15.Take 25 and take away the sum of its digits. What do you get?
  16. 16.?779 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  17. 17.551? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  18. 18.6?39 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  19. 19.Take 41 and take away the sum of its digits. What do you get?
  20. 20.Take 61 and take away the sum of its digits. What do you get?
  21. 21.510? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  22. 22.605? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  23. 23.?159 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.7?72 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.Take 23 and take away the sum of its digits. What do you get?
  26. 26.Take 46 and take away the sum of its digits. What do you get?
  27. 27.582? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.868? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.Take 54 and take away the sum of its digits. What do you get?
  30. 30.?606 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.Take 24 and take away the sum of its digits. What do you get?
  32. 32.Take 26 and take away the sum of its digits. What do you get?
  33. 33.66?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  34. 34.?318 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  35. 35.43?4 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.?30 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  37. 37.Take 19 and take away the sum of its digits. What do you get?
  38. 38.Take 78 and take away the sum of its digits. What do you get?
  39. 39.198? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  40. 40.Take 91 and take away the sum of its digits. What do you get?

Answer key

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

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