Q. 21: A and B are two railway stations 90 km apart. A train leaves A at 9:00 am, heading towards B at a speed of 40 km/hr. Another train leaves B at 10:30 am, heading towards A at a speed of 20 km/hr. The trains meet each other at
Let’s represent the positions of the trains at 9:00 AM
Train from station B will not start till 10:30 AM, meanwhile train A starts from A at 9:00 AM, and travels for 1.5 hours at 40kmph speed. Therefore, by 10:30 AM, train A travels 1.5 × 40 = 60 km towards B.
The positions of the two trains at 10:30 AM will be