A storage tank consists of a circular cylinder with a hemisphere adjoined on either end. If the external diameter of the cylinder be 1.4m and its length be 8m, find the cost of painting it on the outside at the rate of Rs. 10 per `m^2dot`

Explanation

External diameter of cylinder, `D=1.4m` and height, `h=8m`

Now, Radius, `R=0.7m`

Outer S.A of tank = `2pirh+2pir^2`

`2pir(r+h)

`2xx22/7xx0.7(0.7+8)` = `38.28m^2`

As, rate of painting is Rs. `10` per `m^2`

So, Cost of painting for `38.28 m^2` = `38.28xx10`

Hence, Cost of painting is Rs. `382.8`