SSC Selection Post 2025 PYQ — Question 86

Length of the first train = 120 meters

Length of the second train = 80 meters

Speeds = 40 km/h and 60 km/h

Both are moving towards each other.

Relative speed = 40 + 60 = 100 km/h

In meters/second:

$100 \times \frac{5}{18} = \frac{500}{18} = 27.78 \text{ m/s}$

Total distance = 120 + 80 = 200 meters

Time = Distance ÷ Relative speed

$= \frac{200}{27.78} = 7.2 \text{ seconds}$

= 7.2 seconds

Correct answer: (b) 7.2 seconds