← Digit-sum magic lesson New set →

Digit Sum Magic Worksheet

Maths tricks trick 10: Digit-sum magic · Set 97 · 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. 1.588? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  2. 2.Take 77 and take away the sum of its digits. What do you get?
  3. 3.?431 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  4. 4.Take 32 and take away the sum of its digits. What do you get?
  5. 5.Take 79 and take away the sum of its digits. What do you get?
  6. 6.?61 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  7. 7.20?1 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  8. 8.49? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  9. 9.59?5 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  10. 10.?07 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  11. 11.?059 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  12. 12.?181 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  13. 13.350? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  14. 14.?901 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  15. 15.?047 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  16. 16.Take 45 and take away the sum of its digits. What do you get?
  17. 17.66?6 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  18. 18.Take 47 and take away the sum of its digits. What do you get?
  19. 19.?18 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  20. 20.167? 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.Take 50 and take away the sum of its digits. What do you get?
  23. 23.Take 67 and take away the sum of its digits. What do you get?
  24. 24.807? is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  25. 25.?712 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.Take 35 and take away the sum of its digits. What do you get?
  28. 28.3?89 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  29. 29.?867 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  30. 30.56?3 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  31. 31.?65 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  32. 32.67?4 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  33. 33.Take 12 and take away the sum of its digits. What do you get?
  34. 34.Take 14 and take away the sum of its digits. What do you get?
  35. 35.?362 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.Take 22 and take away the sum of its digits. What do you get?
  38. 38.43?8 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?
  39. 39.Take 29 and take away the sum of its digits. What do you get?
  40. 40.?67 is in the 9 times table. One digit is hidden, and it is not 0. What is the hidden digit?

Answer key

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

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