A cylindrical pillar is 50 cm in diameter and 3.5 m in height. Find the cost of painting the curved surface of the pillar at the rate of 12.50 per m2.
Given:
H=3.5 m, R=502=25 cm =25100=0.25 m⇒CSA=2πrh=(2×227×0.25×3.5) m2
=5.5 m2
⇒Cost of painting 1 m2 area = Rs.12.50
⇒Cost of painting 5.5 m2 area
= Rs.5.5×12.50
= Rs.68.75