```Question 110681
You need to re-post this problem after you include the number of boxes of note paper in the first condition.
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However, I did a little analysis and determined that if the first condition was 5 boxes of envelopes and 3 boxes of note paper, you get an answer that doesn't involve fractional parts of cents, so I'll use that number and you can adjust the arithmetic if it turns out to be something else.
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The first thing I like to do when dealing with dollar amounts expressed with decimal fractions is to convert everything to cents.  I'd just rather work with large whole numbers than decimal fractions, and it is easy enough to convert back at the end.
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Let's say that the cost of a box of envelopes is e, and the cost of a box of note paper is n.  Based on the information in the problem (and my assumption) we can say that:
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Eq 1) {{{5e+3n=2595}}}, and
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Eq 2) {{{2e+6n=2238}}}
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Step 1:  Divide Eq 2) by -2
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Eq 3) {{{-e-3n=1119}}}
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Step 2: Add Eq 3) to Eq 1), term by term and solve the result:
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Eq 4) {{{4e=1476}}}
{{{e=369}}}
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Step 3: Substitute this value into either original equation and solve:
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{{{2(369)+6n=2238}}}
{{{6n=2238-738}}}
{{{6n=1500}}}
{{{n=250}}}
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So, Envelopes are \$3.69 per box, and note paper is \$2.50 per box -- given that my assumption about the note paper quantity was correct.```