<PRE><B>Question 806144</B>
a steamer, going downstream in a river, covers the distance between 2 towns in 15 hours. Coming back upstream, it covers this distance in 20 hours. The speed of the water is 3 km/hr. Find the distance between two towns.


Let the speed of the steamer be  x km/h

speed of current = 3km/h

down the river speed = x+3
Time down stream = 15 hours
Distance = 15(x+3)

up the river speed = x-3
time upstream = 20 hours
distance = 20(x-3)

but distance is same both ways

15(x+3)=20(x-3)

15x+45=20x-60

5x=105

x= 21

speed of steamer = 21 km/h


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