document.write( "Question 1042637: I think this is a basic question. But it has been 10 years since I had any algebra and I have to take a placement course for college courses. Here is my problem: \"if the total cost of x apples is b cents, what is a general formula for the cost, in cents, of y apples?\"
\n" ); document.write( "I believe I know the answer to this problem, but I need help in understanding why this is the answer. I can get to \"by/x\" , but I don't remember why I am going through these motions. Is there a law or property that is involved in this problem? \n" ); document.write( "

Algebra.Com's Answer #657632 by ikleyn(52780) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "if the total cost of x apples is b cents, what is a general formula for the cost, in cents, of y apples?
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document.write( "1.  If \"x\" apples cost b cents, then one apple costs  cents.\r\n" );
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document.write( "    Agree?\r\n" );
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document.write( "    Now, if one apple costs  cents, then \"y\" apples cost  cents.\r\n" );
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document.write( "    Did you get it?\r\n" );
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document.write( "2.  Proportions.\r\n" );
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document.write( "    If \"z\" is the cost of \"y\" apples, then you have this proportion\r\n" );
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document.write( "     = .\r\n" );
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document.write( "    Each side is the price of one single apple.\r\n" );
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document.write( "    In proportion, a mean term is the product of the two extreme terms divided  by the other mean term. \r\n" );
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document.write( "    It gives you\r\n" );
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document.write( "    z = .\r\n" );
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document.write( "    Exactly the same as in the first approach.\r\n" );
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\n" ); document.write( "\n" ); document.write( "On proportions, see the lesson\r
\n" ); document.write( "\n" ); document.write( " - Proportions\r
\n" ); document.write( "\n" ); document.write( "in this site.\r
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\n" ); document.write( "\n" ); document.write( "You have also this free of charge online text-book in Algebra-I\r
\n" ); document.write( "\n" ); document.write( " - ALGEBRA-I - YOUR ONLINE TEXTBOOK\r
\n" ); document.write( "\n" ); document.write( "in this site.\r
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