📄 07 - SET-4 (Trains Advanced), p.1
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Two Stations type: Two trains approach from two different stations, usually from opposite directions, and eventually meet.
The distance between two stations A and B is 800 km. A train X starts from A and moves towards B at 40 km/h and another train Y starts from B and moves towards A at 60 km/h. How far from A will they cross each other?
(A) 380 km
==(B) 320 km ==
(C) 300 km
(D) 360 km
For the keyword "How far from X station will the trains meet?", first find the meeting Time, which is the same for both trains because they start travelling towards each other from opposite directions at the same Time. Then, calculate the Distance from station X to the meeting point using the meeting Time and the Speed of the train.
Places A and B are 396 km apart. Train X leaves from A for B and train Y leaves from B for A at the same time on the same day on parallel tracks. Both trains meet after 5125 \frac{1}{2}521 hours. The speed of train Y is 10 km/h more than that of train X. What is the speed (in km/h) of train Y?
(A) 41
(B) 54
==(C) 31 ==
(D) 56
Two trains start from stations A and B and travel towards each other at speeds of 50 km/h and 60 km/h respectively. At the time of their meeting, the second train has traveled 120 km more than the first. The distance between A and B is:
(A) 990 km
==(B) 1320 km ==
(C) 1200 km
In Relative Speed type, when two trains are travelling towards each other from opposite directions and meet, but their starting Times are not given in the question, assume that they started travelling at the same Time. So, start the sum by equating with the Time (i.e., the meeting Time).
The distance between Gwalior and Delhi is 800 km. Rajdhani Express starts from Delhi at 80 km/h. 60 minutes later, Gwalior Express leaves Gwalior for Delhi on parallel tracks at 40 km/h. How far from Gwalior will they cross each other?
(A) 250 km
(B) 360 km
(C) 240 km
- When two objects start traveling at different Times, let the early starter cover some Distance until the late starter starts. Then treat it as a Relative Speed problem with the remaining Distance.
- For the keyword "How far from X station will the trains meet?", first find the meeting Time, which is the same for both trains because they start travelling towards each other from opposite directions at the same Time. Then, calculate the Distance from station X to the meeting point using the meeting Time and the Speed of the train.
P and Q are 48 km away. Two trains running at the speed of 32 km/h and 20 km/h, respectively, start simultaneously from P and Q and travel in the same direction. They meet at a point R beyond Q. The distance QR is:
(A) 126 km
(B) 80 km
(C) 48 km
- QR = 20 * 4 = 80 km.
- In the Meeting/Chasing type, for the chasing scenario, first focus on finding the meeting Time when the chaser catches up to the runner.
- In Relative Speed type, when two objects travel in the same direction, the faster object will always be behind the slower object, allowing the faster object to chase the slower object until both finally meet.