A cylindrical pillar is 50 cm in diameter and 3.5 m in height. Find th

1.	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.
Answer» Height of cylindrical pillar (h) = 3.5 m Radius of circular end of pillar ( r) = 50/2 cm = 25 cm = 0.25 m [As radius = half of the diameter] and [1 m = 100 cm] Curved surface area of cylindrical pillar = 2πrh = 2 x 3.14 x 0.25 x 3.5 = 5.5 Curved surface area of cylindrical pillar is 5.5 m. Cost of whitewashing 1m² is Rs 12.50 Cost of whitewashing 5.5 m² area = Rs. 12.50 x 5.5 = Rs. 68.75 Thus the cost of whitewashing the pillar is Rs 68.75.

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.

Answer»

Height of cylindrical pillar (h) = 3.5 m

Radius of circular end of pillar ( r) = 50/2 cm

= 25 cm

= 0.25 m [As radius = half of the diameter] and [1 m = 100 cm]

Curved surface area of cylindrical pillar = 2πrh

= 2 x 3.14 x 0.25 x 3.5

= 5.5

Curved surface area of cylindrical pillar is 5.5 m.

Cost of whitewashing 1m² is Rs 12.50

Cost of whitewashing 5.5 m² area = Rs. 12.50 x 5.5

= Rs. 68.75

Thus the cost of whitewashing the pillar is Rs 68.75.