Question 1152795
<pre>

GOING                  60          d/60           d

RETURN                 40          d/40           d

DIFFERENCE                         2
</pre>
{{{d/40-d/60=2}}}, and question asks for {{{d/60}}}.


{{{d(1/40-1/60)=2}}}

{{{d(3/120-2/120)=2}}}

{{{d=2*120}}}

{{{d=240}}}

-

{{{240/60=highlight(4)}}}{{{hours}}}