Find the cost of plastering
Answer: (3) 1980
The deep of the well = 22.5 m
The diameter of the well = 7 m
Therefore, the radius of the well = 7/2 = 3.5 cm
Then, the curved surface area of the well = 2 x 22 x 7 x 22.5/7 x 2
= 22.5 x 22
= 495 sq. m
The cost of plastering the inner curved surface at Rs.4 per sq meter
Then, the total cost of plastering the inner curved surface of the well = 495 x 4
= Rs. 1980.
Hence, the correct answer is option (3) Rs. 1980.