Question
A and B are travelling towards each other with a speed
of 30 km/hr and 40 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 = 30:40 = 3:4 Let the distance covered by A and B be 3x km and 4x km According to the question, 4x – 3x = 20 Or, x = 20 Therefore, distance between them before starting = 3x + 4x = 7x = 140 km
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