Multiple choice What is the HCF of 12 , 15 and 24? 1 2 3 6 Reveal answer Fill a bubble to check yourself C Correct answer Explanation 12, 15, 24 Factors of 12 = 2 × 2 × 3 Factors of 24 = 2 × 2 × 2 × 3 Factors of 15 = 3 x 5 HCF = 3