Question 1070375
<pre>            
            SPEED     TIME      DISTANCE

WALK         4        {{{8/4=2}}}       8

JOG          8         t         8t

Totals              t+2        8t+8
</pre>


Question asks for overall speed to be 5 kilometer per hour.
{{{(8t+8)/(t+2)=5}}}


{{{8t+8=5t+10}}}

{{{3t=2}}}

{{{3t/3=2/3}}}

{{{highlight(t=2/3)}}}, forty minutes.




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