### Examples

**Example 1:** Find the HCF of 36, 48 and 60.

**Solution:**

Prime factorization of 36: 36 = 2, 2, 3, 3

Prime factorization of 48: 48 = 2, 2, 2, 2, 3

Prime factorization of 60: 60 = 2, 2, 3, 5

Take the common prime factors and multiply them together to get HCF.

Therefore, HCF(36, 48, 60) = 12.
**Example 2:** Find the HCF of 24, 32 and 40.

**Solution:**

Prime factorization of 24: 24 = 2, 2, 2, 3

Prime factorization of 32: 32 = 2, 2, 2, 2, 2

Prime factorization of 40: 40 = 2, 2, 2, 5

Take the common prime factors and multiply them together to get HCF.

Therefore, HCF(24, 32, 40) = 8.
**Example 3:** Find the HCF of 18, 24 and 30.

**Solution:**

Prime factorization of 18: 18 = 2, 3, 3

Prime factorization of 24: 24 = 2, 2, 2, 3

Prime factorization of 30: 30 = 2, 3, 5

Take the common prime factors and multiply them together to get HCF.

Therefore, HCF(18, 24, 30) = 6.

### Exercise

**1.** HCF(75,100,125) = 25

**2.** HCF(49,98,147) = 49

**3.** HCF(63,77,91) = 7

**4.** HCF(45, 60, 75) = 15

**5.** HCF(56, 72, 84) = 28

**6.** HCF(42, 56, 70) = 14

**7.** HCF(63, 84, 105) = 21

**8.** HCF(80, 100, 120) = 20

**9.** HCF(90, 120, 150) = 30

**10.** HCF(54, 72, 90) = 18