← HCF and LCM lesson New set →

HCF and LCM Worksheet

Quantitative aptitude lesson 1: HCF and LCM · Set 679 · 40 questions
TalentJR

The method (Prime factors): Write each number as a product of primes: 36 = 2 × 2 × 3 × 3. HCF: multiply the primes the numbers share (each as many times as it appears in both). LCM: take every prime the greatest number of times it appears. For two numbers, HCF × LCM = first number × second number.

NameDateTime takenScore ___ / 40
  1. 1.The HCF of two numbers is 4 and their LCM is 168. One of the numbers is 24. What is the other number?
  2. 2.Find the HCF of 15 and 21.
  3. 3.Find the HCF of 12 and 8.
  4. 4.Find the LCM of 8 and 9.
  5. 5.The HCF of two numbers is 3 and their LCM is 42. One of the numbers is 21. What is the other number?
  6. 6.Find the LCM of 7, 4 and 14.
  7. 7.Find the LCM of 20 and 32.
  8. 8.Find the HCF of 55 and 99.
  9. 9.The HCF of two numbers is 3 and their LCM is 45. One of the numbers is 15. What is the other number?
  10. 10.Find the HCF of 28 and 36.
  11. 11.Find the HCF of 9 and 6.
  12. 12.Find the LCM of 12, 3 and 5.
  13. 13.The HCF of two numbers is 3 and their LCM is 84. One of the numbers is 21. What is the other number?
  14. 14.Find the LCM of 9 and 24.
  15. 15.Find the LCM of 28 and 8.
  16. 16.The HCF of two numbers is 3 and their LCM is 30. One of the numbers is 15. What is the other number?
  17. 17.The HCF of two numbers is 5 and their LCM is 105. One of the numbers is 15. What is the other number?
  18. 18.Find the HCF of 56 and 40.
  19. 19.Find the LCM of 30 and 24.
  20. 20.Find the LCM of 5, 6 and 10.
  21. 21.The HCF of two numbers is 3 and their LCM is 84. One of the numbers is 12. What is the other number?
  22. 22.The HCF of two numbers is 7 and their LCM is 42. One of the numbers is 21. What is the other number?
  23. 23.Find the LCM of 3, 7 and 15.
  24. 24.Find the LCM of 5, 9 and 3.
  25. 25.Find the HCF of 20 and 35.
  26. 26.Find the LCM of 42 and 30.
  27. 27.Find the LCM of 28 and 24.
  28. 28.Find the LCM of 8, 3 and 7.
  29. 29.Find the HCF of 50 and 70.
  30. 30.Find the HCF of 21 and 15.
  31. 31.The HCF of two numbers is 3 and their LCM is 126. One of the numbers is 18. What is the other number?
  32. 32.The HCF of two numbers is 4 and their LCM is 224. One of the numbers is 32. What is the other number?
  33. 33.The HCF of two numbers is 7 and their LCM is 98. One of the numbers is 49. What is the other number?
  34. 34.Find the LCM of 12, 10 and 2.
  35. 35.Find the LCM of 32 and 28.
  36. 36.Find the LCM of 11, 6 and 3.
  37. 37.Find the LCM of 8, 15 and 3.
  38. 38.Find the LCM of 40 and 35.
  39. 39.Find the HCF of 18 and 63.
  40. 40.Find the LCM of 18 and 30.

Answer key

  1. 28
  2. 3
  3. 4
  4. 72
  5. 6
  6. 28
  7. 160
  8. 11
  9. 9
  10. 4
  11. 3
  12. 60
  13. 12
  14. 72
  15. 56
  16. 6
  17. 35
  18. 8
  19. 120
  20. 30
  21. 21
  22. 14
  23. 105
  24. 45
  25. 5
  26. 210
  27. 168
  28. 168
  29. 10
  30. 3
  31. 21
  32. 28
  33. 14
  34. 60
  35. 224
  36. 66
  37. 120
  38. 280
  39. 9
  40. 90

Free quantitative aptitude lessons, practice and worksheets at talentjr.in/quantitative-aptitude