Question
Boat ‘R’ travels thrice as fast as boat ‘S’ in
still water. If they start from points 450 km apart and move towards each other, meeting after 5 hours, what is the speed of boat ‘S’ in still water?Solution
ATQ,
Let the still water speed of boat ‘S’ = y km/h
Then, still water speed of boat ‘R’ = 3y km/h
Let stream speed = x km/h
Effective speed = y + 3y = 4y km/h
So, 4y = 450 ÷ 5 = 90
y = 90 ÷ 4 = 22.5
Speed of boat ‘S’ in still water = 22.5 km/h
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