A rectangle has a perimeter of $98 \mathrm{cm}$ and its length is two and a half times its width. Find the width.

A rectangle has a perimeter of $98 \mathrm{cm}$ and its length is two and a half times its width. Find the area of a rectangle.

An athlete takes $5$ rounds of a rectangular park, $80 m$ long and $30 m$ wide. Find the total distance covered by him.

Find the perimeter of a regular pentagon whose each side measures $3.4 cm$

A square of side $8 cm$ and a rectangle of length $16 cm$ have the same area. Find the perimeter of the rectangle.