Question
A boat covers a distance of 150 km while moving in a
downstream in 5 hours. When the boat covers a distance of 60 km in still water in 3 hours, then What will be the distance covered by boat (in km) in upstream in 8 hours.Solution
Let the speed of the boat in still water and speed of the stream will be taken as 'x' km/hr & 'y' km/hr respectively. ATQ,we can say that Speed of the boat in downstream = (x + y) = (150/5) = 30km/hr ....(I) Also, 'x' = (60/3) = 20.....(II) So, from equation (II), we can say that 20 + y = 30 Or, y = 10 So, distance covered in upstream will be = (x - y) x 8 = (20 - 10) x 8 = 80km
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