document.write( "Question 1029405: A women bought an number of items for $90. She realized that if she had bought 10 more for the same money she would have paid 12 less per item. How many items did she buy? \n" ); document.write( "

Algebra.Com's Answer #644479 by Boreal(15235) $\"\"$ $\"About$

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x items * 90/x price per item=90
\n" ); document.write( "90/(x+10) is $12 less than 90/x
\n" ); document.write( "Therefore (90/(x+10))+12=90/x
\n" ); document.write( "multiply everything by (x)(x+10)
\n" ); document.write( "90x+12x^2+120x)=90x+900, clearing fractions.
\n" ); document.write( "12x^2+120x-900=0
\n" ); document.write( "divide everything by 12
\n" ); document.write( "x^2+10x-75=0
\n" ); document.write( "(x+15)(x-5)=0
\n" ); document.write( "x=5, only positive number
\n" ); document.write( "Paid $18 per item for 5 items
\n" ); document.write( "Had she bought 10 more, or 15 altogether, she would have paid $6 per item, which is $12 less. \n" ); document.write( "

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