The ratio between the length and the breadth of a rectangular park is 3 : 2. If a man cycling along the boundary of the park at the speed of 12 km/hr completes one round in 8 minutes, the n the area of the park (in square metre) is :

A. 15360 square metre

B. 153600 square metre

C. 30720 square metre

D. 307200 square metre

Answer: Option B

Solution(By Examveda Team)

$${\text{Perimeter}} = $$   $${\text{Distance covered in 8 minutes}}$$
$$\eqalign{ & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = \left( {\frac{{12000}}{{60}} \times 8} \right)m \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = 1600{\text{ }}\,m \cr} $$
Let the length = 3x metres and breadth = 2x metres
Then,
2 (3x + 2x) = 1600
or, x = 160
Length = 480 m and breadth = 320 m
∴ Area = (480 × 320) m²
           = 153600 square metre