document.write( "Question 1207335: Hi
\n" ); document.write( "Mark bought a number of pens at an average cost of $2.50 He bought another pen for $8.50 and the average cost of the pens became $4.50. How many pens did he buy altogether.
\n" ); document.write( "Thanks \n" ); document.write( "
Algebra.Com's Answer #845159 by josgarithmetic(39616)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "PRICE         HOW MANY        COST\r\n" );
document.write( "$2.5            n             2.5n\r\n" );
document.write( "$8.5            1             8.5*1\r\n" );
document.write( "                            ----------\r\n" );
document.write( "\r\n" );
document.write( "                             2.5n+8.5
\r
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\n" ); document.write( "\n" ); document.write( "Reported Average Price for All these pens combined
\n" ); document.write( "\"%282.5n%2B8.5%29%2F%28n%2B1%29=4.5\"
\n" ); document.write( "and really want the final result for n+1.\r
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\n" ); document.write( "\n" ); document.write( "\"2.5n%2B8.5=4.5n%2B4.5\"\r
\n" ); document.write( "\n" ); document.write( "\"4=2n\"\r
\n" ); document.write( "\n" ); document.write( "\"n=2\"\r
\n" ); document.write( "\n" ); document.write( "So the needed one more pen, \r
\n" ); document.write( "\n" ); document.write( "He bought total of 3 pens. \n" ); document.write( "
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