Multiple choice Find the HCF of 36, 54 and 45. 8 9 10 11 Reveal answer Fill a bubble to check yourself B Correct answer Explanation Factors of 36 are 1, 2, 4, 6, 9, 12, 18, and 36. Factors of 54 are 1, 2, 3, 6, 9, 18, 27, and 54. Factors of 45 are 1, 3, 5, 9, 15, and 45. So, 9 is the HCF.