Perimeter and A...

A floor which measures $$15m\, \times\, 8m$$ is to be laid with tiles measuring $$50cm\, \times\, 25cm$$. Find the number of tiles required.
Further, if a carpet is laid on the floor so that a space of 1 m exists between its edges and the edges of the floor, what fraction of the floor is uncovered.

The shaded portion of the figure, given along side,shows two concentric circles.
If the circumference of the two circles are $$396 \:cm$$ and $$374\: cm$$, find the area of the shaded portion.

The area of a circle is $$394.24$$ $$cm^2$$.  What is  the radius of the circle ?

The circumference of a circular field is $$308 m$$, Find its Area.

The diameter of a circle is $$28 cm$$. Find its circumference

The area enclosed by the circumferences of two concentric circles is $$346.5\, cm^2$$. If the circumference of the inner circle is $$88$$ cm, then the radius of the outer circle is

The radii of two circles are $$25\ cm$$ and $$18\ cm$$. Find the radius of the circle which has a circumference equal to the sum of the circumference of these two circles.

The diameter of a circle is $$28 cm$$. Find the one-fourth of its area.

The area of the cross-section;

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