The inner diameter of a circular well is 3.5 m. It is 10 m deep Find:(

1.	The inner diameter of a circular well is 3.5 m. It is 10 m deep Find:(i) inner curved surface area.(ii) the cost of plastering this curved surface at the rate of Rs. 40 per m^2.
Answer» Given, Inner diameter of circular well = 3.5 m Inner radius = \(\cfrac{3.5}2\) m Depth of well = 10 m i) Inner curved surface area of well = 2πrh = 2\(\times\cfrac{22}7\times\cfrac{3.5}2\times\) 100 = 110 m² ii) Cost of plastering 1m² area = Rs.40 Cost of plastering 110 m² = 40 × 110 = 4400 rs.

The inner diameter of a circular well is 3.5 m. It is 10 m deep Find:(i) inner curved surface area.(ii) the cost of plastering this curved surface at the rate of Rs. 40 per m^2.

Answer»

Given,

Inner diameter of circular well = 3.5 m

Inner radius = \(\cfrac{3.5}2\) m

Depth of well = 10 m

i) Inner curved surface area of well = 2πrh = 2\(\times\cfrac{22}7\times\cfrac{3.5}2\times\) 100 = 110 m²

ii) Cost of plastering 1m² area = Rs.40

Cost of plastering 110 m² = 40 × 110 = 4400 rs.