Time, Speed and Distance Question 7 - CAT 2020
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:
Step-by-Step Explanation
Synchronize the departure times:
Train A leaves at 9:00 am at 40 km/hr. Train B leaves at 10:30 am.
Train A travels alone for 1.5 hours (from 9:00 am to 10:30 am):
Distance covered by A alone = 40 km/hr × 1.5 hours = 60 km
Remaining distance separating them at 10:30 am = 90 − 60 = 30 km
Calculate the meeting timeline:
At 10:30 am, both trains are moving toward each other, so we sum their speeds:
Relative Speed = 40 + 20 = 60 km/hr
Time to meet = 30/60 = 0.5 hours = 30 minutes
Meeting Time = 10:30 am + 30 minutes = 11:00 am
Correct Option: C
💡 FundaMakers Tip:
For any relative speed problem involving different starting times, always synchronize the clocks first. Calculate the head start distance covered by the early mover. Once both entities are active at the same time, apply the standard relative speed formula to find the meeting time.