Question 1101020
<pre>
            SPEED      TIME    DISTANCE

GOING         r        7/r       7

RETURN       r-2       7/(r-2)   7

Total                   3
</pre>


{{{highlight(7/r+7/(r-2)=3)}}}
Solve for r and evaluate r-2.

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algebra steps should lead to {{{3r^2-20r+14=0}}};

{{{r=(20+sqrt(232))/6}}}

{{{r=(10+2*sqrt(29))/3}}}

{{{r=(10+10.77)/3}}}

{{{r=6.72}}}------speed GOING

(May need rechecking)