Question 1139841
<pre>
            SPEED       TIME              DISTANCE

John          r        t=110/r               110

Peter        r+15      t=140/(r+15)          140
</pre>


 {{{110/r=140/(r+15)}}}

--

{{{11/r=14/(r+15)}}}

{{{11(r+15)=14r}}}

{{{11r+165=14r}}}

{{{3r=165}}}

{{{r=55}}},{{{John}}}

{{{Peter}}}, {{{70}}}

--

AVERAGE:  {{{(55+70)/2=highlight(62&1/2)}}}

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