A 400 m long train passes a railway platform in 20 seconds with speed 90 km/hr. What is the length of platform?

A and B are two points in a river. Point X and Y divide the line AB in three equal parts. Let the flow of the river is from A to B. The ratio of the time taken to row from point A to Y and from B to Y is 3 : 4. Find the ratio of the speed of the boat upstream to the flow of the river.

A train take 15 second to cross a pole. If the speed of the train is 60 km/hr, then length of the train is:

A train crosses a pole in 12 second and a bridge of length 170 meter in 36 second. Then the speed of the train is?

Which of the following speeds is maximum ?

Train of 200 meters long takes 18 seconds to cross a man running at 15 kmph in a direction opposite to that of the train. The speed of the train:

Manish walk on the mountain upto a certain distance and ride back taking a total time of 27 minutes. Manish could walk both ways in 45 minutes. How long would it take Manish to ride both ways.