← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 209 · 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 25 and take away the sum of its digits. What do you get?
  2. 2.2?68 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  3. 3.Take 95 and take away the sum of its digits. What do you get?
  4. 4.15?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  5. 5.Take 27 and take away the sum of its digits. What do you get?
  6. 6.?073 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.559? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  8. 8.1?30 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  9. 9.?038 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  10. 10.37?6 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.?968 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  12. 12.Take 62 and take away the sum of its digits. What do you get?
  13. 13.1?4 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  14. 14.654? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  15. 15.?472 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  16. 16.36?5 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  17. 17.?546 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  18. 18.Take 36 and take away the sum of its digits. What do you get?
  19. 19.5?87 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  20. 20.Take 31 and take away the sum of its digits. What do you get?
  21. 21.Take 73 and take away the sum of its digits. What do you get?
  22. 22.Take 11 and take away the sum of its digits. What do you get?
  23. 23.?25 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.40? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.51?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.641? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  27. 27.Take 39 and take away the sum of its digits. What do you get?
  28. 28.?34 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.?059 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  30. 30.?500 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.20?6 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.Take 90 and take away the sum of its digits. What do you get?
  33. 33.82?1 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  34. 34.?194 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  35. 35.61?7 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.50?9 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  37. 37.Take 92 and take away the sum of its digits. What do you get?
  38. 38.4?74 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  39. 39.Take 55 and take away the sum of its digits. What do you get?
  40. 40.5?48 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?

Answer key

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

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