Question 1193084
<br>
You already have two responses from different tutors, both of which are valid, but they both make the solution more complicated than necessary.<br>
To make the solution easier, note that the distance is not needed.  The only information you need, along with the fact that he swims at 2mph, is the fact that the return trip takes three times as long.<br>
So set the problem up like this.<br>
let c be the speed of the current
then 2+c is his speed downstream
and 2-c is his speed upstream<br>
Since his time returning is 3 times his time going downstream, his speed downstream is 3 times his upstream speed:<br>
{{{2+c=3(2-c)}}}
{{{2+c=6-3c}}}
{{{4c=4}}}
{{{c=1}}}<br>
ANSWER: The speed of the current is 1mph<br>