← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 492 · 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 44 and take away the sum of its digits. What do you get?
  2. 2.13?5 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  3. 3.Take 50 and take away the sum of its digits. What do you get?
  4. 4.?480 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  5. 5.70?3 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  6. 6.?78 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.?698 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  8. 8.?609 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  9. 9.Take 30 and take away the sum of its digits. What do you get?
  10. 10.43?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.6?53 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  12. 12.Take 76 and take away the sum of its digits. What do you get?
  13. 13.8?97 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  14. 14.7?75 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  15. 15.81?5 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  16. 16.?014 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  17. 17.Take 33 and take away the sum of its digits. What do you get?
  18. 18.54?9 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  19. 19.4?87 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  20. 20.4?90 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.Take 66 and take away the sum of its digits. What do you get?
  22. 22.47?2 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  23. 23.30?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.Take 11 and take away the sum of its digits. What do you get?
  25. 25.?966 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.?057 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  27. 27.2?50 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.Take 96 and take away the sum of its digits. What do you get?
  29. 29.30?6 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  30. 30.385? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.?30 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.620? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  33. 33.Take 73 and take away the sum of its digits. What do you get?
  34. 34.232? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  35. 35.Take 21 and take away the sum of its digits. What do you get?
  36. 36.?505 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  37. 37.Take 67 and take away the sum of its digits. What do you get?
  38. 38.Take 43 and take away the sum of its digits. What do you get?
  39. 39.8?50 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  40. 40.4?28 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?

Answer key

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

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