document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=214205>Question 214205</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Todd has 48 words to spell for a puzzle. His mother says she will pay him $1.00 for every word he spells correctly but he has to pay her $0.60 for every word he spells incorrectly. If Todd makes $19.20, how many words did he spell correctly?\r<BR>\n" );
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document.write( "Define the variable, create the equation, and solve. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #162091 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=162091\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Todd has 48 words to spell for a puzzle. His mother says she will pay him $1.00 for every word he spells correctly but he has to pay her $0.60 for every word he spells incorrectly. If Todd makes $19.20, how many words did he spell correctly?<BR>\n" );
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document.write( "x = number of words spelled correctly.<BR>\n" );
document.write( "y = number of words spelled incorrectly.<BR>\n" );
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document.write( "number of words spelled correctly plus number of words spelled incorrectly equals 48.<BR>\n" );
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document.write( "x + y = 48<BR>\n" );
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document.write( "x * 1.00 = amount of money he makes if he spells a word correctly.<BR>\n" );
document.write( "y * .60 = amount of money he has to pay back if he spells a word incorrectly.<BR>\n" );
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document.write( "number of words spelled correctly times a dollar minus the number of words spelled incorrectly times 60 cents equals 19.20<BR>\n" );
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document.write( "1.00 * x - .60 * y = 19.20<BR>\n" );
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document.write( "you have 2 equations that need to be solved simultaneously.<BR>\n" );
document.write( "they are:<BR>\n" );
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document.write( "x + y = 48<BR>\n" );
document.write( "x - .6y = 19.20<BR>\n" );
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document.write( "use the first equation to solve for y.<BR>\n" );
document.write( "you get:<BR>\n" );
document.write( "y = 48-x<BR>\n" );
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document.write( "substitute for y in the second equation to get:<BR>\n" );
document.write( "x - .6*(48-x) = 19.2<BR>\n" );
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document.write( "remove parentheses to get:<BR>\n" );
document.write( "x - .6*48 + .6x = 19.2<BR>\n" );
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document.write( "simplify results and combine like terms to get:<BR>\n" );
document.write( "1.6x - 28.8 = 19.2<BR>\n" );
document.write( "add 28.8 to both sides of the equation to get:<BR>\n" );
document.write( "1.6x = 48<BR>\n" );
document.write( "divide both sides of the equation by 1.6 to get:<BR>\n" );
document.write( "x = 30<BR>\n" );
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document.write( "since x+y = 48, then y = 18<BR>\n" );
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document.write( "plug these values into x - .6y = 19.2 to get:<BR>\n" );
document.write( "30 - .6*18 = 30 - 10.8 = 19.2<BR>\n" );
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document.write( "this checks out so the answer is:<BR>\n" );
document.write( "number of questions answered correctly is 30 and number of questions answered incorrectly is 18.<BR>\n" );
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document.write( " </SPAN>\n" );
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