A park is in the shape of a rectangle. Its length and breadth 240 m and 100 m, respectively. At the centre of the park. there is a circular lawn. The area of the park, excluding the lawn is 3904 m2. What is the perimeter (in m) of the lawn? (use π = 3.14)
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 502.4
Area of Rectangle = Length × Breadth, Area of Circle = πr2
According to question,
⇒ Area of park = 240 × 100 = 24000m2
As given the area of the park, excluding the lawn is 3904 m2 it means
⇒ Area of lawn = 24000 - 3904 = 20096m2
⇒ πr2 = 20096
(3.14)r2 = 20096, r2 = 6400, r = 80m
The perimeter (in m) of the lawn = 2πr
⇒ 2 × 3.14 × 80 = 502.4m