Question

11. The cost of polishing a
circular slab of diameter 14m,
if the rate of polishing is Rs. 2
per sq m.*​

Answer 1

Diameter = 14m

2 × radius = 14m

radius = 14 m

2

radius = 7 m

Area of the circular slab = πr²

= 22 × 7m × 7m

7

= [22 × 7]m²

= 154 m²

Rate of polishing per m² = Rs. 2

Rate of polishing 154 m² = Rs. [2 × 154]

= Rs. 308

so, the cost of polishing the circular slab is Rs. 308

Hope it's helpful