Question
A and B are travelling towards each other with a speed
of 40 km/hr and 50 km/hr. If they started at same time and A covered 20 km less distance than B before meeting him, then find the distance between them before starting.Solution
Since, the time taken by A and B is same, therefore the ratio of the distance covered by them will be equal to the ratio of their speeds. Therefore, ratio of the distance covered by A and B = 40:50 = 4:5 Let the distance covered by A and B be 4x km and 5x km According to the question, 5x – 4x = 20 Or, x = 20 Therefore, distance between them before starting = 5x + 4x = 9x = 180 km
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