Question

Two trains running in opposite directions cross a man standing on the platform in 27 sec and 17 sec, respectively and they cross each other in 23 sec. The ratio of their speeds is

Options

• 1 : 3

• 3 : 2

• 3 : 4

• None of these

Answer 1

3 : 2
Explanation:
Let, the speeds of the two trains be x m/s and y m/s, respectively.
Then, the length of the first train = 27x m
and length of the second train = 17y m

∴ ${\displaystyle \frac{27x+17y}{x+y}=23}$

⇒ 27x + 17y = 23x + 23y

⇒ 4x = 6y

∴ ${\displaystyle \frac{x}{y}=\frac{3}{2}}$