Correct Answer: 82 km/hr
Explanation:
Step 1: Convert the speed of the first train to m/s
Speed = 50 km/hr = (50 × 1000) / 3600 = 13.89 m/s
Step 2: Let the speed of the second train be x km/hr
Then, speed in m/s = (x × 1000) / 3600 = x × (5/18) m/s
Step 3: Total length to be covered when trains cross each other = 108 + 112 = 220 m
Relative speed = 13.89 + (5x/18) m/s
Time = Distance / Relative Speed
6 = 220 / (13.89 + (5x/18))
Step 4: Solve the equation
13.89 + (5x / 18) = 220 / 6 = 36.67 (5x / 18) = 36.67 - 13.89 = 22.78 Multiply both sides by 18: 5x = 410.04 x = 410.04 / 5 = 82.01
Answer: 82 km/hr
The speed of the second train is approximately 82 km/hr.
This is a classic time–distance–speed problem involving relative speed when two objects move towards each other. Such problems are common in quantitative aptitude sections of exams like SSC, Bank PO, and Railway Recruitment.
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