### Examples

**Example 1:** Find the HCF of 27, 36 and 45.

**Solution:**

Prime factorization of 27: 27 = 3, 3, 3

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

Prime factorization of 45: 45 = 3, 3, 5

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

Therefore, HCF(27, 36, 45) = 9.
**Example 2:** Find the HCF of 50, 75 and 100.

**Solution:**

Prime factorization of 50: 50 = 2, 5, 5

Prime factorization of 75: 75 = 3, 5, 5

Prime factorization of 100: 100 = 2, 2, 5, 5

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

Therefore, HCF(50, 75, 100) = 25.
**Example 3:** Find the HCF of 72, 96 and 120.

**Solution:**

Prime factorization of 72: 72 = 2, 2, 2, 3, 3

Prime factorization of 96: 96 = 2, 2, 2, 2, 2, 3

Prime factorization of 120: 120 = 2, 2, 2, 3, 5

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

Therefore, HCF(72, 96, 120) = 24.

### Exercise

**1.** HCF(36,48,60) = 12

**2.** HCF(50,70,90) = 10

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

**4.** HCF(16, 24, 32) = 8

**5.** HCF(81, 108, 135) = 27

**6.** HCF(60, 80, 100) = 20

**7.** HCF(48, 64, 80) = 16

**8.** HCF(18, 24, 30) = 6

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

**10.** HCF(88, 110, 132) = 22