<PRE><B>Question 1113230</B>
v*t=distance
(5-c)*t=6
(5+c)*t=10, where c is the current
t=6/(5-c)
t also = (10)/(5+c)
Those two are equal since the times are stated to be equal.
cross multiply
6(5+c)=10(5-c)
30+6c=50-10c
16c=20
c=1.25 mph ANSWER
check
3.75 mph against and takes 6/3.75 or 1.6 hours to go 6 miles.
6.25 mph with and takes 1.6 hours to go 10 miles
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