The area of a circle is $15400 {\mathrm{m}}^2$. Find its circumference in $\mathrm{m}$.

 The area of a quadrant is $A$ ${\mathrm{cm}}^2$, if the radius is $14 \mathrm{c}\mathrm{m}.$ Find the the value of $A$

Find the area of shape$\left(\mathrm{in} {\mathrm{cm}}^2\right)$ correct to one decimal place. $($Use $3.14$ for $\mathrm{\pi })$

Finding the area of shape correct to one decimal place, we get $k c{m}^2$. $($Use $3.14$ for $\mathrm{\pi })$

Write the value of $k$.

Find the area of the shaded portion in ${\mathrm{cm}}^2$.

Covers for cans are stamped out of sheets of metal. How many square centimetres of waste material is there, when the covers are cut from a square $5 \mathrm{c}\mathrm{m}$ wide? $$$($Use $3.14$ for $\mathrm{\pi })$

The given figure shows $4$ identical quadrants in a square. If the area of the shaded part is  $k {\mathrm{cm}}^2$, then find the value of $k$.(Take $\mathrm{\pi }=3.14)$

A sheet of metal has dimensions $56 \mathrm{c}\mathrm{m}$ by $33 \mathrm{c}\mathrm{m}$. It is melted down and recast into discs of the same thickness and radius $7 \mathrm{c}\mathrm{m}$. How many discs will be cast?