Tamil Nadu Board Solutions for Chapter: Mensuration, Exercise 9: Exercise 7.1

The radius and height of a cylinder are in the ratio $5:7$ and its curved surface area is $5500 \mathrm{sq}.\mathrm{cm}$. Find its radius and height.

A solid iron cylinder has total surface area of $1848 \mathrm{sq}.\mathrm{m}$. Its curved surface area is five - sixth of its total surface area. Find the radius and height of the iron cylinder.

The external radius and the length of a hollow wooden log are $16 \mathrm{cm}$ and $13 \mathrm{cm}$ respectively. If its thickness is $4 \mathrm{cm}$ then find its T.S.A in ${\mathrm{cm}}^2$.

$4$ persons live in a conical tent whose slant height is $19 \mathrm{cm}$. If each person require $22 {\mathrm{cm}}^2$ of the floor area, then find the height of the tent in $\mathrm{cm}$ (correct up to two decimal places).

A girl wishes to prepare birthday caps in the form of right circular cones for her birthday party, using a sheet of paper whose area is $5720 {\mathrm{cm}}^2$, how many caps can be made with radius $5 \mathrm{cm}$ and height $12 \mathrm{cm}$.

The radius of a sphere increases by $25\%$. Find the percentage increase in its surface area.

The internal and external diameters of a hollow hemispherical vessel are $20 \mathrm{cm}$ and $28 \mathrm{cm}$ respectively. Find the cost $\left(₹\right)$ to paint the vessel all over at $₹ 0.14 \mathrm{per} {\mathrm{cm}}^2$.

The frustum shaped outer portion of the table lamp has to be painted including the top part. Find the total cost of painting the lampin $₹$, if the cost of painting $1 \mathrm{sq}.\mathrm{cm}$ is $₹2$.