Question

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 1

Here, r = 50 /2 cm = 25 cm = 0.25 m, h = 3.5 m 

Curved surface area of the pillar = 2πrh 

= 2 × 22/ 7 × 0.25 × 3.5 m² = 5.5 m² 

Cost of painting 1 m² = Rs 12.50 

∴ Total cost of painting the curved surface of the pillar 

= Rs 12.50 × 5.5 = Rs 68.75 Ans