Question

The distance between two station howrah and patna is450 km. A train start from 4pm leaves from howrah andmoves towards patna at an average speedof 60km/hr. Another trains moves from patnaat 3:20pm and moves towards howrah at an average speedof 80km/hr. How far fromhowrah the twotrainmeet and at what time?

Answer 1

They will meet 170 km from howrah and at 06:50 pm

Explanation :

Let the distance covered by train from howrah

d₁ = 60t

where t = time taken by train to cover distance d₁ after 4 pm

Let the distance covered by train from patna

d₂ = 80(t + 2/3)            [time to travel = t + 40minutes = t+2/3 hours]

we know that,

d₁ + d₂ = 450

=> 60t +  80(t + 2/3)  = 450

=> 140t + 160/3 = 450

=> t =  1190/420 hours

=> t = 1190 x 60/420 minutes

=> t = 170 minutes = 2 hours  50 minutes

Hence d₁ = 60 x 1190/420 = 170 km

time at which they will meet = 4pm + 2 hours  50 minutes = 6:50pm