Question 1078135
Jacqui commutes 30 mi to her job each day.She finds that if she drives 10<s>mi/</s> MILES per HOUR faster, it takes her 6 minutes less to get to work. Find her new speed!
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The time difference of 6 minutes is  {{{1/10}}} of an hour.

<pre>
             SPEED       TIME              DISTANCE
REGULAR        r        {{{30/r}}}             30
NEW          r+10       {{{30/(r+10)}}}        30
DIFFERENCE               {{{1/10}}}
</pre>


{{{30/r-30/(r+10)=1/10}}}-----Solve this for r, and evaluate r+10.




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A LITTLE MORE DIRECT
<pre>
                   SPEED      TIME        DISTANCE
REGULAR             x-10      30/(x-10)     30
NEW                  x        30/x          30
DIFFERENCE                    1/10
</pre>

Solve for x:
{{{highlight_green(30/(x-10)-30/x=1/10)}}}