Multiple choice

A train X starts from Meerut at $4 $ PM and reached Delhi at $5$ PM. While another train starts from Delhi at $4$ PM and reaches Meerut at $5:30$. The two train will cross each other at ?

  1. $4:36$ PM
  2. $4:42$ PM
  3. $4:48$ PM
  4. $4:50$ PM
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Train X travels from Meerut to Delhi in 1 hour (speed = D/1). Train Y travels from Delhi to Meerut in 1.5 hours (speed = D/1.5). Relative speed is D + D/1.5 = 2.5D/1.5 = 5D/3. They meet at time t = Distance / Relative Speed = D / (5D/3) = 3/5 hours = 36 minutes after 4 PM.

AI explanation

Let the total distance between the cities be D. The first train takes 1 hour, so its speed is D per hour. The second train takes 1.5 hours, so its speed is D/1.5, or 2D/3 per hour. Using the relative speed formula for two objects moving towards each other, their combined speed is D + 2D/3 = 5D/3. The time taken to meet is the total distance divided by their combined speed, so D divided by 5D/3 equals 3/5 of an hour. Converting 3/5 of an hour to minutes gives 36 minutes. Since they start at 4 PM, they cross each other at 4:36 PM.

Keep practicing — related questions