find HCF of 624, 936, n 264

624 = 2 × 2 × 2 × 2 × 3 × 13

936 = 2 × 2 × 2 × 3 × 3 × 13

264 = 2 × 2 × 2 × 3 × 11

So, HCF = 2 × 2 × 2 × 3 = 24