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 Rs 12.50 per m2
Height (h) cylindrical pillar = 3.5 m
Radius (r) of the circular end of pillar = 
= 25 cm
= 0.25 m
CSA of pillar = 2πrh
= 2 * 
* 0.25 * 3.5 m2
= (44 * 0.125) 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
Therefore, the cost of painting the CSA of the pillar is Rs 68.75
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