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

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