<PRE><B>Question 938021</B>
a man can row 15 km downstream in 1 hour and upstream for the same distance in 3 hours.Using the same speed,how far can the man row in 3 hours in still water?
let x=speed of rowboat in still water
let c=speed of current
x+c=speed of rowboat downstream
x-c=speed of rowboat upstream
travel time*speed=distance
..
3(x-c)=15
1(x+c)=15
..
3x-3c=15
x+c=15
..
3x-3c=15
3x+3c=45 (mult. eq. by 3)
add
6x=60
x=10 km/h=speed of rowboat in still water
how far can the man row in 3 hours in still water? 30 km
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