← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 635 · 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.?617 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.Take 19 and take away the sum of its digits. What do you get?
  3. 3.Take 82 and take away the sum of its digits. What do you get?
  4. 4.89?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  5. 5.?488 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  6. 6.502? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.5?70 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  8. 8.Take 56 and take away the sum of its digits. What do you get?
  9. 9.Take 67 and take away the sum of its digits. What do you get?
  10. 10.Take 37 and take away the sum of its digits. What do you get?
  11. 11.72?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  12. 12.Take 50 and take away the sum of its digits. What do you get?
  13. 13.78?2 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  14. 14.?138 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  15. 15.Take 98 and take away the sum of its digits. What do you get?
  16. 16.236? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  17. 17.Take 69 and take away the sum of its digits. What do you get?
  18. 18.Take 30 and take away the sum of its digits. What do you get?
  19. 19.?209 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  20. 20.6?70 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.84?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  22. 22.6?45 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  23. 23.?091 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.2?41 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.Take 27 and take away the sum of its digits. What do you get?
  26. 26.29? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  27. 27.?638 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.6?20 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.?44 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  30. 30.8?59 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.3?63 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.6?51 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  33. 33.?910 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  34. 34.?386 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  35. 35.28?1 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.13?5 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  37. 37.Take 88 and take away the sum of its digits. What do you get?
  38. 38.3?46 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  39. 39.Take 41 and take away the sum of its digits. What do you get?
  40. 40.Take 48 and take away the sum of its digits. What do you get?

Answer key

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

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