Question 1165441
k, the time needed for Kirk working alone

<pre>
PERSON            RATE
Jeff              1/(k-3)
Kirk              1/k
Combined          1/10
</pre>

The size of the wall 75 feet only represents the ONE JOB.  How MUCH of the job is not emphasized in the description.


Solve for k, in {{{1/(k-3)+1/k=1/10}}}.

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{{{k^2-23k+30=0}}}

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General solution for quadratic equation formula gives 21.6 hours for Kirk to do the one job by himself.