<PRE><B>Question 1064437</B>
s=35 mph
c is current speed
(35-c)(0.6)=distance gone upstream, since 0.6 of an hour is 36 minutes.
(35+c)(0.4)=distance gone downstream, since 0.4 of an hour is 24 minutes.
These distances are equal.
21-0.6c=14+0.4c
7mph=c ANSWER
28 mph upstream for .6 hour=16.8 miles
42 mph downstream for .4 hour=16.8 miles check
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