V K Raman and S N Sharma Solutions for Exercise 4: EXERCISE 31(D)

The area of a ring formed by two concentric circles is $880{\mathrm{cm}}^2$. If the diameter of the smaller circle is $18\mathrm{cm}$, find the diameter of the bigger circle.

$\mathrm{Use}: \mathrm{\pi }=\frac{22}{7}$

The side of a square is $44\mathrm{cm}$. A circle has the same circumference as the perimeter of the square. if the difference between their areas is $k {\mathrm{cm}}^2$.

Then find the value of $k$.

$\mathrm{Use}: \mathrm{\pi }=\frac{22}{7}$

The figure consists of a rectangle with semi-circles at the two breadth, on the outside. If the dimensions of the rectangle are $60\mathrm{cm}$ by $42\mathrm{cm}$ and the area enclosed is $k {\mathrm{cm}}^2$. 

Then find the value of $k$.

$\mathrm{Use}: \mathrm{\pi }=\frac{22}{7}$

The given figure is a square of side $5.6\mathrm{cm}$ with two semi-circles inscribed inside, touching each other. Calculate the perimeter of the shaded part.

$\mathrm{Use}: \mathrm{\pi }=\frac{22}{7}$

The given figure is a square of side 5.6 cm with two semi-circles inscribed inside, touching each other. If the area of the shaded part is $k {\mathrm{cm}}^2$. 

Then find the value of $k$.

$\mathrm{Use}: \mathrm{\pi }=\frac{22}{7}$

The figure is formed by a square with four three-fourth circles described outside as shown. Given that the side of the square is $14\mathrm{cm}$, find the perimeter of the shaded part.

$\mathrm{Use}: \mathrm{\pi }=\frac{22}{7}$

The figure is formed by a square with four three-fourth circles described outside as shown. Given that the side of the square is 14 cm and the area of the shaded part is $k {\mathrm{cm}}^2$. 

Then find the value of $k$.

$\mathrm{Use}: \mathrm{\pi }=\frac{22}{7}$

The area of a ring is $770{\mathrm{cm}}^2$• If the circumference of the bigger circle is $132\mathrm{cm}$, find the circumference of the smaller circle. 

$\mathrm{Use}: \mathrm{\pi }=\frac{22}{7}$