A train departs from Delhi to Kolkata at a speed of 60 kmph at 12 p.m. noon. Another train starts from Delhi to Kolkata at a speed of 75 kmph at 2 p.m. At what distance from Delhi both will meet?
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$600 km.$
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$540 km.$
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$500 km.$
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$400 km.$
A
Correct answer
Explanation
When the second train starts at 2 p.m., the first train has a 2-hour head start and has covered 60 × 2 = 120 km. The relative speed of the two trains is 75 - 60 = 15 kmph. Time to catch up = 120/15 = 8 hours. Distance from Delhi = 75 × 8 = 600 km (or 60 × 10 = 600 km). Both trains meet 600 km from Delhi.