Question 1068895
<pre>
                speed        time          distance

Fast             5           t               d

Slow             4           t+35/60         d

</pre>


{{{35/60=5*7/(5*12)=7/12}}}


-
{{{system(5t=d,4(t+7/12)=d)}}}


{{{t=d/5}}}
-
{{{4t+7/3=d}}}
{{{4d/5+7/3=d}}}

{{{3*5(4d/5+7/3)=3*5*d}}}

{{{12d+35=15d}}}

{{{35=3d}}}

{{{d=35/3}}}

{{{highlight(d=11&2/3)}}}