Question

A train leaves at 10 am from Delhi at the speed of 60km/hr to Agra, another train which is an express train leaves from Delhi at 120 km/hr at 2 pm to Agra following the same route , at what time does two trains meet each other ?
1. 4 pm
2. 5 pm 
3. 7 pm
4. 6 pm
5. 10 pm

Answer 1

Correct Answer - Option 4 : 6 pm

Let the normal train be train A and the express train be train B 

From 10 am to 2 pm distance travelled by train A = 4 × 60 = 240 km

Let the train A moves a distance of x km after 2 pm before they meet ,

Now the express train B have to travel (240 + x) km in the same time as the time taken by train A to travel x km ;

⇒ (240 + x)/120 = x/60

⇒ 240 + x = 2x

⇒ x = 240 km

V time taken to travel 240 km by train A = 240 /60 = 4hr

⇒ They meet 4 hr after 2pm i.e. 6pm