A train travelling at the speed of x km/h crossed a 300 m long platform in 30 seconds, and overtook a man walking in the same direction at 6 km/h in 20 seconds. What is the value of x?
Answer & explanation
Correct answer: option 2
Length of the platform is 300m = 0.3 km
Speed of a man is 6 km/hr
Let the length of train = a m
Speed of the train = b km/hr
According to the question,
b × \(\frac{5}{18}\) = \(\frac{a + 300}{30}\)
b × \(\frac{5}{18}\) = (\(\frac{a}{30}\) + 10) ----(1)
and
(b - 6) × \(\frac{5}{18}\) = \(\frac{a}{20}\) ----(2)
on solving both we get
b = 96
So , The value of b is 96 km/hr