Three numbers are in the ratio of 2 : 3 : 5 and their LCM is 90 . Find their HCF.

9 1 6 3

3

Let the number be 2x, 3x and 5x. LCM of (2x, 3x and 5x) = 2 × 3 × 5 × (x) ⇒ 30x According to the question, 30x = 90 ⇒ x = 3 So, numbers are 6, 9, 15 6 = 2 × 3 9 =  3 × 3  15  =3  × 5 So, HCF = 3