ANSWER: A
Explanation:
Relative speed of the train to man = (162 – 18)
= 144km/hr
Convert km/hr into m/s
144km/hr = (144 * 5 /18) m/s
= 40 m/s
When the train passes a boy, it covers the distance which is equal to its own length in the above
relative speed
Given that it takes 24se for the train to cross a boy
So length of the train = relative speed * time
= 40 *36
= 1440 m
Speed of train = 162 km/hr
= (162 * 5 / 18)m/s
= 45 m/s
When the train crosses the bridge it over the distance which is equal to the sum of length of trains & bridge
So the sum of length of train & bridge = speed * time
= 45 * 60
= 2700 m
i.e., length of the train + length of bridge = 2700m
1440 + length of bridge = 2700
length of bridge = 1260 m
the length of the bridge & train are 1260 and 1440m