MrMicrostrip wrote:
A person travel 285 km in 6 hour. The part it travel by bus at 40 km/hr which include stoppage time of 10%. Second part is travel by train at 55 km/hr. Find Stoppage time?
The wording here is a little questionable. The journey had two parts: first part (including the stoppage time) and second part. It should be clarified that the 'average speed' during the first part is 40 km/hr (which accounts for the stoppage time in its calculation). I did assume that this is what the question meant since it says "at 40 km/hr which includes stoppage time of 10%", still I wasn't entirely sure whether it means that the 'first (btw, this word is missing) part of the journey' includes stoppage time or 'calculation of 40 km/hr' includes stoppage time. Anyway, assuming that it means the stoppage time is accounted for in the calculation of 40 km/hr,
Average speed during the entire journey = 285 km/6 hrs = 47.5 km/hr
Since 47.5 is exactly in the middle of 40 and 55, time taken to cover first part = time taken to cover second part (when calculating the weighted average of speed, time is the 'weight')
Hence time taken to cover first part = 6/2 hrs = 3 hrs.
Stoppage time = 10% of 3 hrs = 10% of 180 mins = 18 mins
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