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A boat covers 24 km upstream and 36km downstream in 6hours, while it covers 36 km upstream and 24 kmdownstream in 6 22 hours. The velocity of the current is |
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Answer» Let rate upstream = x km/h and rate downstream = y km/hThen,(24/x) + (36/y) = 36 ------(i)and (36/x) + (24/y) = 13/2 -------(ii)Adding (i) and (ii),60((1/x) + (1/y)) = 25/2=> (1/x) + (1/y) = 5/24 -------(iii)Subtracting (i) from (ii)12((1/x) - (1/y)) = 1/2=> (1/x) - (1/y) = 1/24 --------(iv)Adding (iii) and (iv)2/x = 6/24=> x = 8So (1/8) + (1/y) = 5/24=> y = 12Speed Upstream = 8 km/h andSpeed Downstream = 12 km/hSo,Velocity of Current = (1/2) * (12-8)= 2 km/h |
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