document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=842757>Question 842757</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Mixture Word problem\r<BR>\n" );
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document.write( "Mix together M&Ms and trail mix. The M&Ms are $7.00 per pound. And Trail Mix is $15.00 per pound. How many of each to get 480 pounds that would cost to be $8.00 per pound?\r<BR>\n" );
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document.write( "My 2 equations that I came up with are:<BR>\n" );
document.write( "x+y=480<BR>\n" );
document.write( ".7x+.15y=.8*480\r<BR>\n" );
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document.write( "so I did the subsitution method to solve. I solved the first problem as <BR>\n" );
document.write( "Y=-x+480.\r<BR>\n" );
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document.write( "then my second equation came out to be .7x+.15y=384 \r<BR>\n" );
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document.write( "Then I subsituted the first equation into the second equation and got<BR>\n" );
document.write( ".7x +.15(-x+480)=384... I distributed the .15 to the -x and 480. The new equation came to be...<BR>\n" );
document.write( ".7x-.15x+72=384.\r<BR>\n" );
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document.write( "then I combined the x's. subtracted 72 from both sides and got:<BR>\n" );
document.write( ".55x=312<BR>\n" );
document.write( "Then divided .55 to get x by it self, there for x=567.27\r<BR>\n" );
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document.write( "I know from here i would put the x= value into the first problem of x+y=480 But I know x is wrong... did i set it up wrong? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #507748 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=507748\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> you are multiplying x by .7 when you should be multiplying x by 7.<BR>\n" );
document.write( "same with y and same with 480.\r<BR>\n" );
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document.write( ".7 is 70 cents a pound.<BR>\n" );
document.write( "you want 7 dollars a pound which is 7.\r<BR>\n" );
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document.write( "when you solved for y, you got y = x + 480.<BR>\n" );
document.write( "that should have been y = 480 - x.\r<BR>\n" );
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document.write( "let me go through it and you'll see what and where you went wrong.\r<BR>\n" );
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document.write( "x + y = 480 is the first equation<BR>\n" );
document.write( "7x + 15y = 8(480) is the second equation.\r<BR>\n" );
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document.write( "you want to solve by substitution.<BR>\n" );
document.write( "start with x + y = 480<BR>\n" );
document.write( "subtract x from both sides of this equation to get y = 480 - x<BR>\n" );
document.write( "substitute for y in the second equation to get:\r<BR>\n" );
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document.write( "7x + (15 * (480 - x)) = (8 * 480)<BR>\n" );
document.write( "simplify to get:<BR>\n" );
document.write( "7x + (15 * 480) - (15 * x) = (8 * 480)<BR>\n" );
document.write( "simplify further to get:<BR>\n" );
document.write( "7x + 7200 - 15x = 3840<BR>\n" );
document.write( "combine like terms to get\"<BR>\n" );
document.write( "-8x + 7200 = 3840<BR>\n" );
document.write( "subtract 7200 from both sides of this equation to get:<BR>\n" );
document.write( "-8x = 3840 - 7200<BR>\n" );
document.write( "simplify to get:<BR>\n" );
document.write( "-8x = -3360<BR>\n" );
document.write( "multiply both sides of this equation by -1 to get:<BR>\n" );
document.write( "8x = 3360<BR>\n" );
document.write( "divide both sides of this equation by 8 to get:<BR>\n" );
document.write( "x = 420\r<BR>\n" );
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document.write( "replace x in the equation of x + y = 480 to get 420 + y = 480<BR>\n" );
document.write( "subtract 420 from both sides of this equation to get y = 480 - 420 which simplifies to y = 60\r<BR>\n" );
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document.write( "you have x = 420 and y = 60<BR>\n" );
document.write( "7 * 420 + 15 * 60 = 3840 for 480 pounds of mix.<BR>\n" );
document.write( "divide 3840 by 480 to get:<BR>\n" );
document.write( "cost per pound for the mix is equal to 8.\r<BR>\n" );
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document.write( "numbers check out so the solution is good.\r<BR>\n" );
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document.write( "two mistakes that were obvious were:<BR>\n" );
document.write( "you used .7 and .8 and .15 rather than 7 and 8 and 15.<BR>\n" );
document.write( "you said y = x + 480 when you should have said y = 480 - x\r<BR>\n" );
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document.write( "i didn't check the rest out but, if you follow my logic, you should be able to see where else you went wrong, if  you did anything else wrong.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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