Question
Speed of a boat in still water to speed of boat in
upstream is 15: 13. If the boat can travel 340 km in downstream in 10 hours, then find the time taken by the boat to cover 50 km in still water.Solution
Let speed of boat in still water and speed of boat in upstream be lsquo;15xrsquo; km/h and lsquo;13xrsquo; km/h, respectively. Speed of stream = 15x ndash; 13x = 2x km/h Speed of boat in downstream = 15x + 2x = 17 km/h So, 17x = 340/10 =gt; x = 2 Speed of boat in still water = 15 times; 2 = 30 km/h Desired time = 50/30 x 60 = 100 minutes
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