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A & B are 2 stations in between 90 miles and a train starts from A to B. At the same time a bird starts from B towards the moving train. On reaching the train, the Bird immediately turn back and return to B. The bird makes these journeys from B to the train and back to B continuously till the train reaches B. How many miles did the bird travels. (i) If the speed of the train is 60 miles/hr and speed of the bird is 90 miles/hr. (ii) If the speed of the train is 90 miles/hr and speed of the bird is 60 miles/hr
Distance b/w A and B = 90 Miles
(i)Speed of train (A to B) = 60 Miles/Hr
Speed of bird (B to A) = 90 Miles/Hr
Relative Speed = 60 + 90 = 150 Miles/Hr (As they are moving in opposite direction)
Time to cover the distance (90 miles) = 90/150 = 3/5 hr = 36 min
Distance covered by bird when it moves towards A = 90 x 3/5 = 54 miles
Total distance covered by bird = 2 x 54 = 108 miles (As bird takes u turn so distance covered will be double)
(ii) Same as first case try on your own
