Question

If radii of two circular cylinders are in the ratio 3:4 and their heights are in the ratio

6:5, find the ratio of their curved surfaces.​

Answer 1

Answer:

Let the radius be r and R

Let height be h and H

r/ R = 3/4

h/H = 6/5

Ratio of CSA = 2πrh/2πRH

= r/R * h/H

= 3/4 * 6/5

= 9: 10

Answer 2

Answer:

r1 = 3 , r2 = 4 , h1 = 6 , h2 = 5

CSA OF CYLINDER = 2PIERH

SO, IT will be

csa 1 = 2 × 22 /7 × 3 × 6

csa 2 = 2× 22÷7 × 4 × 5

ratio = csa1÷csa2

= 9:10 is the ans.