A train Lucknow Express leaves station A at 4 am and

Solution

ATQ, Let distance between station A and B = 'd' km. Speed of Lucknow express = (d/3) Speed of Kanpur express = (2d/5) Relative speed = (d/3) + (2d/5) = (11d/15) Now, trains meet each other after 6am, when train Kanpur express starts its journey. So, distance travelled by Lucknow express from 4am to 6am =[2 × (d/3)]= (2d/3) Remaining distance = [d - (2d/3)] = d/3 Hence time taken to cross each other = [(d/3)/(11d/15)] = (5/11)hrs (5/11) × 60 = 27 min (approx) Thus, both of them cross each other at = 6:27am