document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=150808>Question 150808</A>: <I><SPAN STYLE=\"word-break: break-all;\">  Problem: A survey of 615 teenagers found that 44% of the boys and 35% of the girls would like to be taller. Altogether, 231 teenagers in the survey wished they were taller.\r<BR>\n" );
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document.write( "(1)   Set up a system of equations to model this scenario.\r<BR>\n" );
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document.write( "(2)   Use determinants and Cramer’s rule to determine how many boys and how many girls were in the survey.\r<BR>\n" );
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document.write( "(3)   Answer the question in (2) by using inverse matrices.\r<BR>\n" );
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document.write( "(4)   Compare the two methods. When might one method be better than another method for solving a system?  \r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #110740 by </B><A HREF=/tutors/aboutme.mpl?userid=mangopeeler07><B>mangopeeler07(462)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mangopeeler07><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=110740\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> (1)   Set up a system of equations to model this scenario.\r<BR>\n" );
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document.write( "b=# of boys<BR>\n" );
document.write( "g=# of girls\r<BR>\n" );
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document.write( ".44b+.35g=231<BR>\n" );
document.write( "b+g=615<BR>\n" );
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document.write( "(2) how many boys and how many girls were in the survey. \r<BR>\n" );
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document.write( "Solve for g in the second equation<BR>\n" );
document.write( "g=615-b\r<BR>\n" );
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document.write( "plug that in for g in the top equation<BR>\n" );
document.write( ".44b+.35(615-b)=231\r<BR>\n" );
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document.write( "Distribute<BR>\n" );
document.write( ".44b+215.25-.35b=231\r<BR>\n" );
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document.write( "Combine like terms<BR>\n" );
document.write( ".09b+215.25=231\r<BR>\n" );
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document.write( "Subtract 215.25 from both sides<BR>\n" );
document.write( ".09b=15.75\r<BR>\n" );
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document.write( "Divide each side by .09<BR>\n" );
document.write( "b=175\r<BR>\n" );
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document.write( "g=615-b<BR>\n" );
document.write( "g=615-175<BR>\n" );
document.write( "g=440\r<BR>\n" );
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document.write( "# of boys=175<BR>\n" );
document.write( "# of girls=440 </SPAN>\n" );
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