← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 929 · 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. 1.2?32 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.?608 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  3. 3.Take 27 and take away the sum of its digits. What do you get?
  4. 4.Take 28 and take away the sum of its digits. What do you get?
  5. 5.91? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  6. 6.Take 26 and take away the sum of its digits. What do you get?
  7. 7.72?0 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  8. 8.Take 42 and take away the sum of its digits. What do you get?
  9. 9.?212 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  10. 10.1?24 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.?362 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  12. 12.?431 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  13. 13.899? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  14. 14.1?51 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  15. 15.?254 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  16. 16.?025 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  17. 17.?425 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  18. 18.Take 43 and take away the sum of its digits. What do you get?
  19. 19.108? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  20. 20.40? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  21. 21.58?1 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  22. 22.Take 93 and take away the sum of its digits. What do you get?
  23. 23.6?53 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  24. 24.662? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.?895 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  26. 26.5?97 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  27. 27.?413 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  28. 28.?019 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.?242 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  30. 30.Take 45 and take away the sum of its digits. What do you get?
  31. 31.?049 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.436? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  33. 33.Take 51 and take away the sum of its digits. What do you get?
  34. 34.Take 19 and take away the sum of its digits. What do you get?
  35. 35.?808 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  36. 36.7?30 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  37. 37.4?21 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  38. 38.2?00 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  39. 39.782? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  40. 40.?132 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?

Answer key

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

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