1.  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. 230 m
B. 240 m
C. 260 m
D. 320 m
E. None of these

Answer: Option A

Explanation:

Relative speed = (120 + 80) km/hr

   = 200 x 5 m/sec
18

   = 500 m/sec.
9

Let the length of the other train be x metres.

Then, x + 270 = 500
9 9

x + 270 = 500

x = 230.