The capacity of a cylindrical tank is 246.4 litres. If the height is 4 metres, what is the diameter of the base ?

A. 1.4 cm

B. 2.8 cm

C. 14 cm

D. 28 cm

E. None of these

Answer: Option D

Solution(By Examveda Team)

Volume of the tank = 246.4 litres = 246400 cm³
Let the radius of the base be r cm
Then,
$$\eqalign{ & \left( {\frac{{22}}{7} \times {r^2} \times 400} \right) = 246400 \cr & \Rightarrow {r^2} = \left( {\frac{{246400 \times 7}}{{22 \times 400}}} \right) \cr & \Rightarrow {r^2} = 196 \cr & \Rightarrow r = 14 \cr} $$
∴ Diameter of the base = 2r = 28 cm