A train x running at 74 km/h crosses another train y running at 52 km/h in the opposite direction in 12 seconds. If the length of y is two - third that of x, then what is the length of x ( in m )?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 252
A train x running at 74 km/h crosses another train y running at 52 km/h in the opposite direction in 12 seconds.
The length of y is two-thirds that of x.
When two trains cross each other, their relative speed will be the sum of their speed.
Distance = Time × speed
Relative speed = (74 + 52) = 126 km/h = 126 × (5/18) = 35 m/s
Time taken to cross each other is 12 seconds.
Total distance covered = (12 × 35) = 420 m
The length of y is two-thirds that of x.
Let, the length of the train x is x meter.
ATQ -
(x + (2x/3) = 420
x = 420 × (3/5) = 252
The length of the train X is 252 m.