Question 1157117
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Let x be the average rate moving to parents (in miles per hour).

Then the average rate moving back is x-14 mph.


{{{552/x}}}  is the time going to.

{{{552/(x-14)}}}  is the time going back.


The time equation is

    {{{552/x}}} + {{{552/(x-14)}}} = 23   hours.


Cancel the factor 23 in both sides

    {{{24/x}}} + {{{24/(x-14)}}} = 1.


Reduce to the standard form quadratic equation and solve it.


Then evaluate x-14.
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