← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 243 · 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. 1.184? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.Take 11 and take away the sum of its digits. What do you get?
  3. 3.813? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  4. 4.27?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  5. 5.Take 25 and take away the sum of its digits. What do you get?
  6. 6.?993 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.57?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  8. 8.527? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  9. 9.317? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  10. 10.Take 94 and take away the sum of its digits. What do you get?
  11. 11.Take 68 and take away the sum of its digits. What do you get?
  12. 12.53?5 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  13. 13.?821 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  14. 14.6?60 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  15. 15.4?86 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  16. 16.?106 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  17. 17.25?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  18. 18.57?4 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  19. 19.Take 29 and take away the sum of its digits. What do you get?
  20. 20.559? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.13? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  22. 22.Take 48 and take away the sum of its digits. What do you get?
  23. 23.5?50 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.6?5 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.620? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.Take 97 and take away the sum of its digits. What do you get?
  27. 27.5?40 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.?361 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.2?14 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  30. 30.Take 24 and take away the sum of its digits. What do you get?
  31. 31.2?20 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.249? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  33. 33.15?9 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  34. 34.Take 35 and take away the sum of its digits. What do you get?
  35. 35.2?29 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.Take 49 and take away the sum of its digits. What do you get?
  37. 37.?460 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  38. 38.47?5 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  39. 39.?730 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  40. 40.Take 58 and take away the sum of its digits. What do you get?

Answer key

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

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