Question

The cost of painting the curved surface area of a cylindrical pillar of height 10 m and radius 3.5 m at the rate of ₹ 10 per sq. meter is :
(Take pi=$\frac{22}{7}$)

Answer 1

Curved Surface area of the pillar = 2πrh

$=2\times \frac{22}{7}\times 3.5\times 10$

$=220m^2$

So, the total cost = CSA of pillar $\times$ Cost per m${}^2$ = ₹ 220 $\times$ 10 = ₹ 2200.