Question

. Standing on the side of a railway track a man
found that two trains of same length crossed him
in opposite directions in 18 seconds and 12
seconds respectively. What time will the trains
take to cross each other?​

Answer 1

Let’s say both are L meters long.

We can say that their speeds are L/18 and L/12.

• combined distance =2L (L+L)

• 5L/36 (L/18 + L/12);

• Time = 2L / (5L/36) = 14.4 seconds