Question
A boat takes half the time to move a certain distance
downstream than upstream. the ratio of the boat's speed in still water and that of the current is.Solution
. Let the speed of boat in still water =B and speed of stream =S Speed in Downstream =B+S Speed in Upstream =B-S ATQ- B+S=D/T … (1) B-S=D/2T … (2) Solve Equation (1) and (2) B=3D/4T, S=D/4T B/S=3/1 B:S=3:1 Alternate – Downstreamupstream T1:2 S2:1 Speed of B in still water(B)=(B+S)/2=3/2 Spped of stream(current)(S)=(B-S) =1/2 Ratio of B And S= 3:1
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