Radhika runs along the boundary of a rectangular park at the rate of 12 km/hr and completes one full round in 15 minutes. If the length of the park is 4 times its breadth , the area of the park is?
Correct Answer: 360000 m2
Explanation:
Speed = 12 x (5/18) m/sec
=10/3 m/sec there4; perimeter = (10/3) x 15 x 60 m=3000 m
∵ 2( a + 4a) = 3000 m
⇒ a = 300 m
So, length = 1200 m and breadth = 300 m ∴ Area = (1200 x 300 ) m2 = 360000m2