Question 1110697
1.{{{500Y+750W=55000}}} <-- Total cost
2.{{{Y+W=100}}} <-- Total number of reams
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Multiply eq. 2 by 500 and subtract from eq. 1,
{{{500Y+750W-500Y-500W=55000-50000}}}
{{{250W=5000}}}


Solve for W then use either equation to solve for Y.