Question

A train leaves Pune at 7:30 am and reaches Mumbai at 11:30 am. Another train leaves Mumbai at 9:30 am and reaches Pune at 1:00 pm. Assuming that the two trains travel at constant speeds, at what time do the two trains cross each other?

(a) 10:20 am

(b) 11:30 am

(c) 10:26 am

(d) data not sufficient

Answer 1

Answer is : (c) 10:26 am

Let the distance between Pune and Mumbai be x km.

Time taken by 1st train = 4 h

∴ Speed of 1st train = x/4 km/h

Time taken by 2nd train = 7/2 h

∴ Speed of 2nd train \(=\frac x{(7/2)}\) = 2x/7 km/h

1st train starts from 7 : 30 am and 2nd train starts from 9 : 30 am.

Distance travelled by 1st train in 2 h = x/2 km

Let they meet at time t.

∴ They meet at 9:30+56 = 10:26 am