Two trains running in opposite directions cross a man standing on the platform in 27 seconds and 17 seconds respectively and they cross each other in 23 seconds. The ratio of their speeds is:u=27s v=17s Cross = 23s. l1 = 27x. l2 = 17y. 23 = l1 + l2/x + y 23 = 27x + 17y/x + y. 23x + 23y = 27x + 17y. 4x - 6y = 0. 4x = 6y. x/y = 6/4. x/y = 3/2.
