Two trains, 232 m and 248 m in length, are running in opposite directions.

Solution

Length of first train = 232 m
Length of second train = 248 m

Total distance to be covered while crossing each other:

 232 + 248 = 480 m

Speeds of the trains:

First train = 51 km/h
Second train = 57 km/h

Since they move in opposite directions, relative speed:

 51 + 57 = 108  km/h

Convert speed into m/s:

$108 \times \frac{5}{18} = 30 \text{ m/s}$

Time required:

$\text{Time} = \frac{\text{Distance}}{\text{Speed}}$

$= \frac{480}{30}$

= 16 seconds

Correct option: 16 seconds