motion problem
posted by MNHS MNHS on .
Ric can row upstream against a current at 6kph in 10 hrs while it will take him only 4 hrs going back. how far does he go upstream?
(w/ solution pls... tnx)

rate of paddling in still water  x km/h
speed of the river  y km/h
xy = 6
x = y+6
distance uprstream = 6(10) = 60 km
distance downstream = 4(x+y) = 4(y+6 + y)
= 8y + 24
8y + 24 = 60
y = 4.5
x = 10.5
Actually I did a lot of extra work.
The question was , how far does he go upstream
all I needed was 10(6) = 60 km
btw, in metric we say km/h not kph