Question 1186013
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Sam and Justin together can do a work in 2 days. 
If they had to work separately, the time taken by Justin to do the work would be more than that of Sam by 3 days. 
In how many days cam Justin do the work alone? (Applying quadratic equations)
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<pre>
Sam = x days

Justin = (x+3) days.


The combined rate equation is


    {{{1/x}}} + {{{1/(x+3)}}} = {{{1/2}}}.


The solution can be easily guessed MENTALLY:  x = 3 days.


<U>ANSWER</U>.  Sam can complete this job in 3 days, working alone.

         Justin can complete this job in 3+3 = 6 days, working alone.


<U>CHECK</U>.  {{{1/3}}} + {{{1/(3+3)}}} = {{{1/3 + 1/6}}} = {{{2/6 + 1/6}}} = {{{3/6}}} = {{{1/2}}}.    ! Correct !
</pre>

Solved.


Alternatively,  &nbsp;you can reduce equation  &nbsp;(1)  &nbsp;to the standard quadratic equation form
and solve it formally  &nbsp;EITHER  &nbsp;using the quadratic formula  &nbsp;OR  &nbsp;by factoring.



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To see other similar solved problems, look into the lesson

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/Rate-of-work-word-problems/Using-quadr-eqns-to-solve-word-problems-on-joint-work.lesson>Using quadratic equations to solve word problems on joint work</A> 

in this site.