EXERCISE 11.3

If the cost of polishing a circular table-top of diameter $1.6 \mathrm{m}$ is $₹k$ at the rate of polishing $₹15/{\mathrm{m}}^2$, then find the value of $k$ . (Take $\mathrm{\pi }=3.14$)

Shazli took a wire of length $44 \mathrm{c}\mathrm{m}$ and bent it into the shape of a circle. If the same wire is bent into the shape of a square. Which figure encloses more area, the circle or the square? (Take $\mathrm{\pi }=\frac{22}{7}$)

From a circular card sheet of radius $14 \mathrm{c}\mathrm{m},$ two circles of radius $3.5 \mathrm{c}\mathrm{m}$ and a rectangle of length $3 \mathrm{c}\mathrm{m}$ and breadth $1 \mathrm{cm}$ are removed (as shown in the following figure). If the area of the remaining sheet is $k {\mathrm{cm}}^2$, then find the value of $k.$ (Take $\mathrm{\pi }=\frac{22}{7}$)

A circle of radius $2 \mathrm{c}\mathrm{m}$ is cut out from a square piece of an aluminium sheet of side $6 \mathrm{c}\mathrm{m}.$ If the area of the left-over aluminium sheet is $k {\mathrm{cm}}^2$, then find $k$? (Take $\mathrm{\pi }=3.14$)

A circular flower bed is surrounded by a path $4 \mathrm{m}$ wide. The diameter of the flower bed is $66 \mathrm{m}.$ If the area of this path is $k {\mathrm{m}}^2$, then find the value of $k.$ ($\mathrm{\pi }=3.14$)

A circular flower garden has an area of $314 {\mathrm{m}}^2.$ A sprinkler at the centre of the garden can cover an area that has a radius of $12 \mathrm{m}.$ Will the sprinkler water the entire garden (yes/no)? (Take $\mathrm{\pi }=3.14$)

How many times a wheel of radius $28 \mathrm{c}\mathrm{m}$ must rotate to go $352 \mathrm{m}$? (Take $\mathrm{\pi }=\frac{22}{7}$)

The minute hand of a circular clock is $15 \mathrm{c}\mathrm{m}$ long. If the tip of the minute hand moves $k \mathrm{cm}$ in $1$ hour, then find the value of $k$. (Take $\mathrm{\pi }=3.14$)