Question 1095402
Total travel time was 3.5 hours.
Same distance going A to B as B to A.


<pre>
            SPEED      TIME        DISTANCE

A to B        30       {{{d/30}}}          d

B to A        40       {{{d/40}}}          d

Total                  {{{3&1/2}}}
</pre>

Solve for d in  {{{d/30+d/40=3&1/2}}}.


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{{{d(1/30+1/40)=7/2}}}

{{{d(2/30+2/40)=7}}}

{{{d(1/15+1/20)=7}}}

{{{d(4+3)=420}}}

{{{d=420/7=(6*7*10)/7}}}

{{{highlight(d=60)}}}