How many seconds will a 450 metre long train take to cross a man running with a speed of 6 km/hr in the direction of the moving train if the speed of the train is 60 km/hr?	Choose the correct choice.
A) 25  B) 30  C) 40  D) 45  E) 60

Rationale: explanation : speed of train relatively to man = ( 60 - 6 ) km / hr = 54 km / hr = ( 54 x 5 / 18 ) m / sec = 15 m / sec time taken to pass the man = ( 450 / 15 ) sec = 30 sec . answer : b
Answer: B