A vessel of the conical shape of radius $14 \mathrm{cm}$ and slanted height $20 \mathrm{cm}$ is to be coloured. What is the cost of painting at a rate of  ₹$3/{\text{cm}}^2$ . Take $\pi =\frac{22}{7}$

Concept: We know the curved surface area of a cone $=\pi rl$

For the given conical vessel, $r=14 \mathrm{cm}$ and $l=20 \mathrm{cm}$

Hence, the curved surface area of vessel $=\pi rl$$=\frac{22}{7}\times 14\times 20$$=880{ \mathrm{cm}}^2$

Now, the cost of painting $1{ \mathrm{cm}}^2$ area $=₹ 3$

Then, the cost of painting $880{ \mathrm{cm}}^2$ area $=880\times 3$= $₹ 2640$.

Hence, the total cost of painting the vessel is $₹ 2640$.