Find the cost of a cylinder of radius 14 m and height 3.5 m when the cost of its metal is Rs. 50 per cubic meter :

Answer: Option B

Volume :
$$\begin{array}{rl}& =\pi r^{2}h\\ & =\left(\frac{22}{7}\times 14\times 14\times 3.5\right)m^3\\ & =2156m^3\end{array}$$
∴ Cost of the cylinder :
$$\begin{array}{rl}& =\text{Rs}\text{.}\left(2156\times 50\right)\\ & =\text{Rs}\text{. 107800}\end{array}$$