Prove that the cost of levelling the ground in the form of a triangle having the sides 51 m, 37 m and 20 m at the rate of Rs 3 per `m^2` is Rs. 918.

Find the cost of laying grass in a triangular field of sides 50 m, 65 m and 65 m at the rate of Rs 7per m^2

Find the cost of sinking tube well 280 m deep having diameter 3 m at the rate of Rs 3.60 per m^2 ?

True/False: If the sides of a triangular field measure 51 m, 37 m and 20 m, then the cost of levelling it at Rs 5 per m^2 is 1540

Find the cost of digging a cuboidal pit 8 m long, 6 m broad and 3 m deep at the rate of Rs 30 per m^3 .

Find the ost of painting 12 pillars each of dimeter 48 cm and height 7 m at the rate of Rs.2.50 per m^2 .

Find the cost of fencing a rectangular park of length 250 m and breadth 175 m at the rate of Rs. 12 per m.

Find the cost of colour washing the four walls of a room whose length is 8 cm, breadth is 7 m and height is 6 m at the rate of Rs 30 per square metre.