← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 695 · 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 40 and take away the sum of its digits. What do you get?
  2. 2.2?99 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  3. 3.Take 37 and take away the sum of its digits. What do you get?
  4. 4.790? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  5. 5.Take 90 and take away the sum of its digits. What do you get?
  6. 6.Take 81 and take away the sum of its digits. What do you get?
  7. 7.7?16 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  8. 8.Take 98 and take away the sum of its digits. What do you get?
  9. 9.?172 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  10. 10.24?1 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.Take 22 and take away the sum of its digits. What do you get?
  12. 12.76?4 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  13. 13.?772 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  14. 14.555? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  15. 15.Take 61 and take away the sum of its digits. What do you get?
  16. 16.?832 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  17. 17.154? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  18. 18.400? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  19. 19.2?17 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  20. 20.439? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.?48 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  22. 22.Take 33 and take away the sum of its digits. What do you get?
  23. 23.897? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.?749 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.?448 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.66?1 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  27. 27.4?05 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.8?79 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.Take 36 and take away the sum of its digits. What do you get?
  30. 30.Take 66 and take away the sum of its digits. What do you get?
  31. 31.?433 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.Take 87 and take away the sum of its digits. What do you get?
  33. 33.Take 59 and take away the sum of its digits. What do you get?
  34. 34.278? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  35. 35.?259 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.?103 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  37. 37.?295 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  38. 38.?159 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  39. 39.Take 65 and take away the sum of its digits. What do you get?
  40. 40.Take 64 and take away the sum of its digits. What do you get?

Answer key

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

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