document.write( "Question 1198317: Hi
\n" ); document.write( "John paid $118.40 for 40 books and pens. He sold 6 pens. Then the same number of pens and books left.
\n" ); document.write( "Each book costs 80 cents more than each pen. How much did he pay for the books.
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Algebra.Com's Answer #831912 by ikleyn(52788) $\"\"$ $\"About$

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\n" ); document.write( "John paid $118.40 for 40 books and pens. He sold 6 pens.
\n" ); document.write( "Then the same number of pens and books left.
\n" ); document.write( "Each book costs 80 cents more than each pen. How much did he pay for the books.
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document.write( "Total books plus pens is 40.\r\n" );
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document.write( "Take off 6 pens from 40 items - you will get 40-6 = 34 pens plus books,\r\n" );
document.write( "and there is the same number of books and pens in 34 items.\r\n" );
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document.write( "Hence, there were 17 books and 17+6 = 40-17 = 23 pens in the original collection.\r\n" );
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document.write( "Let x be the price for the book, in dollars.\r\n" );
document.write( "Then the price for the pen is (x-0.8) dollars.\r\n" );
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document.write( "Now write the total money equation\r\n" );
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document.write( "    17x + 23(x-0.8) = 118.40.\r\n" );
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document.write( "Simplify and find x\r\n" );
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document.write( "    17x + 23x = 118.40 + 23*0.8\r\n" );
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document.write( "       40x    =      136.8\r\n" );
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document.write( "         x    =      136.8/40 = 3.42 dollars.\r\n" );
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document.write( "Thus, John paid  17*3.42 = 58.14 for the books.    ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved, with full explanations.\r
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