Question 1203188
This may NOT be the most effective or neatest way to handle the problem:
<pre>
                 Boxes            CupcakesInBox   CountCupcakes

BIG BOX         (5/8)b               c+7         (5/8)b(c+7)

SMALL BOX            b                 c           bc

Total                                             1200
</pre>
{{{system((5/8)b(c+7)-bc=240,and,(5/8)b(c+7)+bc=1200)}}}


Simplifiable and and is system of two unknowns in two equations.

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NOTICE THAT THIS SYSTEM APPEARS TO BE IN  A FORMAT OF

{{{system(X-Y=240,X+Y=1200)}}}
which might be helpful.


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Solving this


{{{2X=1440}}}
{{{X=720}}}


{{{2Y=960}}}
{{{Y=480}}}


and then back-substituting 


{{{system(bc=480,and,(5/8)b(c+7)=720)}}}


{{{system(bc=480,and,b(c+7)=1152)}}}


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{{{bc+7b=1152}}}
{{{480+7b=1152}}}
{{{7b=1152-480}}}
{{{7b=672}}}

{{{highlight(b=96)}}}----which only means that 96 big boxes were used.


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Would indicate 5 cupcakes in each small box.