A cylindrical tank of diameter 35 cm is full of water. If 11 litres of water is drawn off, the water level in the tank will drop by :

A. $$10\frac{1}{2}{\text{ cm}}$$

B. $$11\frac{3}{7}{\text{ cm}}$$

C. $$12\frac{6}{7}{\text{ cm}}$$

D. $$14{\text{ cm}}$$

Answer: Option B

Solution(By Examveda Team)

Let the drop in the water level be h cm
Then,
$$\eqalign{ & \Rightarrow \frac{{22}}{7} \times \frac{{35}}{2} \times \frac{{35}}{2} \times h = 11000 \cr & \Rightarrow h = \left( {\frac{{11000 \times 7 \times 4}}{{22 \times 35 \times 35}}} \right){\text{ cm}} \cr & \Rightarrow h = \frac{{80}}{7}{\text{ cm}} \cr & \Rightarrow h = 11\frac{3}{7}{\text{ cm}} \cr} $$