Question
A boat moves 25km upstream and 39km downstream in 8
hours. It travels 35km upstream and 52km downstream in 11 hours. What is the speed of the stream if it travels at a uniform speed?Solution
Let the speed of boat in still water =B and speed of stream =S then – ATQ- 
Solving (4)-(3) B-S=5km/h B+S=13km/h  Speed of Stream (S)=13-5/2=4km/h
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