List of top General Aptitude Questions on Problem on Trains

A train leaves Station A at 8:00 AM and travels towards Station B at a speed of \(60\) km/h. Another train leaves Station B towards Station A at 9:00 AM at a speed of \(90\) km/h. The distance between the stations is \(390\) km. At what time will the two trains meet?
A train running at 72 km/h crosses a pole in 20 seconds. The length of the train is:
A train 120 meters long takes 9 seconds to cross a platform 180 meters long. What is the speed of the train in km/h?
A train running at the speed of 80 km/h crosses a 350 m long tunnel in 36 seconds. What is the length of the train (in meters)?
Let \( L_1, L_2 \) be two regular languages and \( L_3 \) a language which is not regular. Which of the following statements is/are always TRUE?