Question
Train 'R' starts from Lucknow to Kanpur at 5:00 a.m. Train
'S' starts from Kanpur to Lucknow at 7:00 a.m., traveling at 50 km/h. They cross each other at 12:00 noon. The distance between the cities is 550 km. Find the speed of train 'R'.Solution
ATQ,
Let the speed of train 'R' be 'x' km/h
Distance covered alone = 2 × x = 2x
Time together = 5 hours
ATQ;
5 × (50 + x) = 550 - 2x
Or, 250 + 5x = 550 - 2x
Or, 300 = 7x
So, x = 42.86
So, speed of train 'R' = 42.86 km/h
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