A train 420 m long, running with a speed of 63 km/hr will pass a tree in?
Pick one
A) 15
B) 16
C) 17
D) 20
E) 24

Rationale: "speed = 63 * 5 / 18 = 35 / 2 m / sec time taken = 420 * 2 / 35 = 24 sec answer : option e"
Answer: E