Question 530762
A boat travels 15 miles upstream and returns.
 If the boat travels 14 mph in still water, find the speed of the current if the total trip takes 2 hours and 20 minutes.
:
Let c = the speed of the current
then
(14+c) = effective speed downstream
and
(14-c) = effective speed upstream
:
Change 2 hrs 20 min to {{{7/3}}} hrs
:
Write a time equation: time = dist/speed
:
Upstream time + downstream time = 2 hrs 20 min
{{{15/(14-c)}}} = {{{15/(14+c)}}} = {{{7/3}}}