Question

In a building there are $48$ cylindrical pillars.The radius of each pillar is $28$cm and height is $4m$.Find the total cost of pointing the curved surface area of all pillars at the rate of $Rs.8$ per $m^2$

Answer 1

$\because r=28cm=0.28mh=4m$

curved surface area of a cylindrical pillars is given as;

$CSA=2\pi rh$
$=2.\frac{22}{7}.0.28.4$
$=7.04m^2$

cost of painting the CSA of each pillar$=8\times 7.04$$=Rs56.32$

therefore total cost of painting 48 pillars$=48\times 56.32$$=Rs2703.36$