Testing Quizzes Quantitative Testing

Question:
Two trains enter a tunnel from opposite ends simultaneously. The speeds of the trains are 54 kmph and 72 kmph. After 30 seconds, the trains completely cross each other. After 20 more seconds, the slower train is just out of the tunnel.

What is the length of the faster train?

Option A):
300
Option B):
250
Option C):
200
Option D):
500

Correct Answer is Option A):
300