Question

Two trains Duronto and Rajdhani start from Delhi and Mumbai every day at 8 AM and reach their destinations at 6 PM and 11 PM respectively. But one day Duronto got in an accident at 12 Noon and stopped at the same spot for the day. Find at what time the Duranto will meet Rajdhani on that day.
1. 4 pm 
2. 5 : 30 pm
3. 6 pm
4. 5 pm

Answer 1

Correct Answer - Option 4 : 5 pm

Given: 

Time taken by Duranto to cover the distance = 10 hour 

Time taken by Rajdhani to cover the distance = 15 hour 

Duronto  travel time for that day = 4 hour 

Formula used:

Time = Distance / Speed 

 Calculation

⇒ let distance between Delhi and Mumbai = 30  KM(LCM of 10 and 15)

⇒ Speed of Duronto = 30/10 = 3 Km/h

⇒ Speed of Rajdhani = 30/15 = 2 Km/h

⇒ Relative speed = 3+2 = 5 Km/h (as they are running in opposite direction)

⇒ Total distance traveled by both the train before accident = 4 × 5 = 20 Km

⇒ The remaining distance, which covered by only Rajdhani = 10 Km

⇒ Time taken by Rajdhani to cover the remaining distance = 10/2 = 5 hour 

∴ The two trains will meet at 5 PM.