20 + x/2 = x 20 = x/2 x = 40 meters.
A 270 metres long train running at the speed of 120 kmph crosses another train running in opposite direction at the speed of 80 kmph in 9 seconds. What is the length of the other train?
A 500 yard long train, travelling at 90 mph, enters a tunnel of four and a half miles in length.
How long will elapse between the moment the front of the train enters the tunnel and the moment the end of the train clears the tunnel?
