Explanation

1. Divide 3239 by 2923:

$$3239÷2923=1\text{(remainder = 3239 - 2923 = 316)}$$

2. Now, divide 2923 by 316:

$$2923÷316=9\text{(remainder = 2923 - 9 × 316 = 2923 - 2844 = 79)}$$

3. Now, divide 316 by 79:

$$316÷79=4\text{(remainder = 316 - 4 × 79 = 316 - 316 = 0)}$$

Since the remainder is 0, the H.C.F is 79.