Examples
Example 1: Find the HCF of 35 and 45.
Solution:
Prime factorization of 35: 35 = 5, 7
Prime factorization of 45: 45 = 3, 3, 5
Take the common prime factors and multiply them together to get HCF.
Therefore, HCF(35, 45) = 5.
Example 2: Find the HCF of 30 and 75.
Solution:
Prime factorization of 30: 30 = 2, 3, 5
Prime factorization of 75: 75 = 3, 5, 5
Take the common prime factors and multiply them together to get HCF.
Therefore, HCF(30, 75) = 15.
Example 3: Find the HCF of 21 and 49.
Solution:
Prime factorization of 21: 21 = 3, 7
Prime factorization of 49: 49 = 7, 7
Take the common prime factors and multiply them together to get HCF.
Therefore, HCF(21, 49) = 7.
Exercise
1. HCF(18,27) = 9
2. HCF(36,42) = 6
3. HCF(60,75) = 15
4. HCF(56, 140) = 28
5. HCF(84, 96) = 12
6. HCF(60, 90) = 30
7. HCF(28, 42) = 14
8. HCF(48, 64) = 16
9. HCF(38, 95) = 19
10. HCF(15, 90) = 15