Question
A train covers a distance of 84 km at the speed of 42
km/h the next 45 km distance covers with a speed of 30 km/h and last 60 km with the speed of 40 km/h find the average speed of the train?Solution
Since the train covers different distance with different speeds. So, Average speed = Total Distance/Total Time Total distance = 84 + 45 + 60 = 189 km Time1 = 84/42, Time2 = 45/30 & Time3 = 60/40 Total Time = 84/42 + 45/30 + 60/40 Therefore, Average Speed = 189/(84/42 + 45/30 + 60/40) = 37.8 km/hr
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