document.write( "Question 1168573: I need help figuring out what the equation should be for this word problem. This is the word problem: \r
\n" ); document.write( "\n" ); document.write( "Lyle sold two types of benches: stained and unstained. The unstained benches cost $20 each and the stained cost $32 each. If Lyle sold 21 benches last month (stained and unstained combined) and collected a total of $600, how many unstained benches did he sell?\r
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Algebra.Com's Answer #793187 by ikleyn(52786) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "            Such problems usually go in one of two possible modifications.\r
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\n" ); document.write( "\n" ); document.write( "            One modification asks about the number of the benches of each of the two types.\r
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\n" ); document.write( "\n" ); document.write( "            If so, then the approach showed you by other tutor is justified and robust.\r
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\n" ); document.write( "\n" ); document.write( "            The other modification may ask you about the number of some special type of bunches - about unstained benches,
\n" ); document.write( "            for example, as it is in your case.\r
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\n" ); document.write( "\n" ); document.write( "            For such modification, the use of systems of two equations IS NOT justified - - - there is MORE SIMPLE, shorter and
\n" ); document.write( "            MORE STRAIGHFORWARD method.\r
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\n" ); document.write( "\n" ); document.write( "            I show it below in my solution.\r
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document.write( "Let x be the number of unstained benches.\r\n" );
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document.write( "Then, OBVIOUSLY, the number of stained benches is (21-x) :\r\n" );
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document.write( "    you simply subtract that \"x\" from the total.\r\n" );
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document.write( "Now you can write the  \"total money equation\"\r\n" );
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document.write( "    20x + 32*(21-x) = 600  dollars.\r\n" );
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document.write( "    |    This single equation is EXACTLY what you ask about in your post.  |\r\n" );
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document.write( "Now, you did not ask to solve it;\r\n" );
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document.write( "    however, I will do it for you to show how simple the steps are.\r\n" );
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document.write( "Simplify this equation\r\n" );
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document.write( "    20x + 32*21 - 32x = 600\r\n" );
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document.write( "    32*21 - 600 = 32x - 20x\r\n" );
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document.write( "     72         = 12x\r\n" );
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document.write( "      x         =  = 6.\r\n" );
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document.write( "That's all.  The solution is just completed,\r\n" );
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document.write( "and the ANSWER is  6 unstained benches.\r\n" );
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\n" ); document.write( "\n" ); document.write( "The job is done, and, as you see, I used only one single equation,
\n" ); document.write( "instead of using the system of two equations.\r
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\n" ); document.write( "\n" ); document.write( "I hope that I answered your question in full.\r
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\n" ); document.write( "\n" ); document.write( "If you have questions, don't hesitate to post them to me.\r
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\n" ); document.write( "\n" ); document.write( "Happy learning (!)\r
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