document.write( "Question 1208177: Hi
\n" ); document.write( "Mr Thomas spent $1972 on cars and dolls. He bought 3 times as many cars as dolls. Each doll cost $10 more than each car. She paid $476 more for the cars than the dolls. What is the cost of a doll. \n" ); document.write( "

Algebra.Com's Answer #846413 by josgarithmetic(39616) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "                 PRICE          QTY         COST\r\n" );
document.write( "\r\n" );
document.write( "CARS              p              3d          3pd\r\n" );
document.write( "\r\n" );
document.write( "DOLLS             p+10           d          d(p+10)\r\n" );
document.write( "\r\n" );
document.write( "Total                                        1972\r\n" );
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\r
\n" ); document.write( "\n" ); document.write( "\"She paid $476 more for the cars than the dolls.\"\r
\n" ); document.write( "\n" ); document.write( " $\"3pd-d%28p%2B10%29=476\"$ \r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Very interesting to notice the sum of two expressions and then the difference of
\n" ); document.write( "those same two expressions.\r
\n" ); document.write( "\n" ); document.write( " $\"system%283pd%2Bd%28p%2B10%29=1972%2C3pd-d%28p%2B10%29=476%29\"$ \r
\n" ); document.write( "\n" ); document.write( "-\r
\n" ); document.write( "\n" ); document.write( " $\"3pd%2Bpd%2B10d=1972\"$
\n" ); document.write( " $\"4pd%2B10d=1972\"$
\n" ); document.write( " $\"2pd%2B5d=986\"$
\n" ); document.write( "-
\n" ); document.write( " $\"3pd-pd-10d=476\"$
\n" ); document.write( " $\"2pd-10d=476\"$
\n" ); document.write( " $\"pd-5d=238\"$ \r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "system: $\"system%282pd%2B5d=986%2Cpd-5d=238%29\"$ \r
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\n" ); document.write( "\n" ); document.write( "Easier if kept in the form $\"system%282pd%2B5d=986%2C2pd-10d=476%29\"$ because now easy to eliminate for pd
\n" ); document.write( "to solve for d.\r
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\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " $\"15d=510\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"highlight%28d=34%29\"$ ----------This is how many dolls bought.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " $\"pd-5d=238\"$
\n" ); document.write( " $\"pd=238%2B5d\"$
\n" ); document.write( " $\"p=%28238%2B5d%29%2Fd\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"p=%28238%2B5%2A34%29%2F34\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"p=12\"$ ---------car price\r
\n" ); document.write( "\n" ); document.write( "Doll is $10 more than a car, so $\"p%2B10=highlight%2822%29\"$ . Price of a doll\r
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\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "-----------------------\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "d=34 so p=12.\r
\n" ); document.write( "\n" ); document.write( "check:
\n" ); document.write( "3pd+d(p+10)=1972 ?
\n" ); document.write( "3*12*34+34(12+10)
\n" ); document.write( "1224+748
\n" ); document.write( "1972
\n" ); document.write( "checks correctly. \n" ); document.write( "

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