A farmer connects a pipe of internal diameter 25 cm from a canal into a cylindrical tank in his field, which is 12 m in diameter and 2.5 m deep. If water flows through the pipe at the rate of 3.6km/hr, in how much time will the tank be filled? Also, find the cost of water if the canal department charges at the rate of Rs 0.07 per m3.

Given,


Internal diameter of the pipe = 25 cm


Radius (r) of the pipe =


Diameter of the cylindrical tank = 12 m


Radius (R) of the tank = 6 m


Height (h) of the tank = 2.5 m


In 1 hour water comes out of the pipe = 3.6 km = 3600 m


Let the total hrs = n


Volume of the water coming out of the pipe in n hrs = volume of the cylindrical tank



= 6 × 6 × 2.5


3600 n = 36 × 2.5 × 8 × 8


100 n = 8 × 8 × 2.5


1000 n = 8 × 8 × 25


n = = 1.6 hrs


n = 1 hrs 36 minutes


Now calculate the cost;


Cost of the water = Volume of the cylindrical tank × 0.07


= = 19.80 rs


So,


Total time required to fill the tank is 1 hr 36 minutes and the cost is 19.80 rs.


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