Perimeter and A...

Two concentric circles form a ring. The inner and outer circumferences of the ring are $50\dfrac{2}{7}\ m$ and $75\dfrac{3}{7}\ m$ respectively. Find the width of the ring.

If the base and altitude of a parallelogram are doubled, what happens to the area compared to the original one?

Find the area of a ring shaped region enclosed between two concentric circles of radii $20$ cm and $15$ cm.

Find the area of a parallelogram having base $4$ cm and height $2$ cm.

The circumference of a circle is $31.4\ cm$. Find the area of the circle? (Take $\pi=3.14$)

Find the area  of the circular park of Janakpuri whose circumference is 77m77m

Find the area of a circle whose radius is $6$ $cm$.

If the perimeter of a circle is $132$ cm, find its area.

One diagonal of a parallelogram is $7cm$ and the perpendicular distance of this diagonal from either of the outlying vertices is $27cm$. The area of the parallelogram (in sq.cm) is:

The radius of a circular wheel is $1.75\ m$. The number of revolutions that it will make in covering $11\ kms$ is: