5. Five mark exercise problems II

1. A container open at the top is in the form of a frustum of a cone of height 16 \(cm\) with radii of its lower and upper ends are 8 \(cm\) and 20 \(cm\) respectively. Find the cost of milk which can completely fill a container at the rate of \(₹40\) per litre.

 

Answer:

 

Cost of milk that will fill the container \(=\) \(₹\)

 

[Note: Round off the cost to two decimal places.]

 

 

2. A hemi-spherical tank of radius \(1.75\) \(m\) is full of water. It is connected with a pipe which empties the tank at the rate of \(7\) litre per second. How much time will it take to empty the tank completely?