← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 221 · 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. 1.161? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.58?7 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  3. 3.251? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  4. 4.Take 61 and take away the sum of its digits. What do you get?
  5. 5.3?18 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  6. 6.15?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.Take 78 and take away the sum of its digits. What do you get?
  8. 8.841? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  9. 9.7?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  10. 10.?255 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.Take 65 and take away the sum of its digits. What do you get?
  12. 12.7?92 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  13. 13.Take 32 and take away the sum of its digits. What do you get?
  14. 14.257? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  15. 15.Take 33 and take away the sum of its digits. What do you get?
  16. 16.Take 16 and take away the sum of its digits. What do you get?
  17. 17.?100 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  18. 18.92? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  19. 19.Take 87 and take away the sum of its digits. What do you get?
  20. 20.?618 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.?019 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  22. 22.?206 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  23. 23.16?5 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.2?40 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.78?4 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.4?77 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  27. 27.Take 84 and take away the sum of its digits. What do you get?
  28. 28.Take 43 and take away the sum of its digits. What do you get?
  29. 29.Take 21 and take away the sum of its digits. What do you get?
  30. 30.?194 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.8?57 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.857? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  33. 33.?110 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  34. 34.806? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  35. 35.1?48 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.29?3 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  37. 37.3?92 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  38. 38.1?42 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  39. 39.6?81 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  40. 40.Take 46 and take away the sum of its digits. What do you get?

Answer key

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

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