document.write( "Question 1193922: Marge purchased x bicycle helmets and y tire pumps. Each helmet cost $15.00 and each pump cost $7.00. She purchased a total of 21 items and spent $243.00. How many helmets did Marge buy? \n" ); document.write( "

Algebra.Com's Answer #825981 by ikleyn(52781) $\"\"$ $\"About$

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\n" ); document.write( "Marge purchased x bicycle helmets and y tire pumps.
\n" ); document.write( "Each helmet cost $15.00 and each pump cost $7.00.
\n" ); document.write( "She purchased a total of 21 items and spent $243.00.
\n" ); document.write( "How many helmets did Marge buy?
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document.write( "Since the problem asks only about helmets, I would solve it using one unknown and one equation,\r\n" );
document.write( "instead of the system.\r\n" );
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document.write( "Let the number of helmets be x; then the number of tire pumps is (21-x).\r\n" );
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document.write( "Now write the total money equation\r\n" );
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document.write( "    15x + 7*(21-x) = 243  dollars.\r\n" );
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document.write( "Simplify and find x\r\n" );
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document.write( "    15x + 147 - 7x = 243\r\n" );
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document.write( "    15x - 7x = 243 - 147\r\n" );
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document.write( "        8x   =    96\r\n" );
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document.write( "         x   =    96/8 = 12.\r\n" );
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document.write( "ANSWER.  12 helmets.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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