Question

the radii of two right circular cylinder are in the ratio 2:3 and their Heights are in the ratio 5:4 .
calculate the ratio of their curved surface areas and also the ratio of their volumes

Answer 1

Hii ✋

Let radius of 1st right circular cylinder be r1 and that of 2nd circular cylinder be r2.
So,
r1:r2 = 2:3
Similarly let the heights of 1st and 2nd cylinders be h1 and ho respectively.
So,
h1:h2 = 5:4

Now,
Let r1 and r2 be 2x and 3x respectively.
Let h1 and h2 be 5x and 4x respectively.
Curved surface are of 1st cylinder/Curved surface are of 2nd cylinder = 2πr1h1/2πr2h2 =r1h1/r2h2 = 2x × 5x/3x × 4x = 10/12 = 5/6 = 5:3