Question

a well with 7m diameter is 10m deep find the cost of plastering its inner c.s.a at the rate of rupees 30 per m^2

Answer 1

This is the answer... Hope it helps you

Answer 2

$Diameter = 7m \\ \\ Radius = \: \frac{diameter}{2} \\ \\ Radius = \frac{7}{2} m \\ \\ \\ C.S.A = 2\pi \: rh \\ \\ = 2 \times \frac{22}{7} \times \frac{7}{2} \times 10 \\ \\ = 220 {m}^{2}$


The cost of plastering inner curved surface area at the rate of Rs. 30 per m square
= 220 X 30
= Rs. 6600