A train traveling at 72 kmph crosses a platform in 32 seconds and a man standing on the platform in 18 seconds. What is the length of the platform in meters?  Choose the correct choice from the following answers:
A) 280 meters
B) 360 meters
C) 420 meters
D) 600 meters
E) can not be determined

Rationale: "speed of train = 72 * ( 5 / 18 ) = 20 m / s lets consider the man as a stationery point on the platform . crossing the point gives us the length of the train . lt = 20 * 18 = 360 m . crossing the platform gives us the length of trainlength of platform . l ( t + p ) = 20 * 32 = 640 m . so , length of platform = 640 - 360 = 280 m imo , answer a"
Answer: A