document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=278427>Question 278427</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A disc jockey must play 16 commercial spots during 1 hour of a radio show.  Each commercial is either 30 seconds or 60 seconds long.  If the total commercial time during 1 hour is 13 min, how many 30-second commercials were played that hour?  How many 60-second commercials? \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 #202610 by </B><A HREF=/tutors/aboutme.mpl?userid=Stitch><B>Stitch(470)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Stitch><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=202610\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let A = 30 sec. Commercial<BR>\n" );
document.write( "Let B = 60 Sec. Commercial\r<BR>\n" );
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document.write( "*Note I am using Minutes in my equations and not seconds ( 1 min = 60 sec)\r<BR>\n" );
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document.write( "Equation 1: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+%2B+B+=+16 ALIGN=MIDDLE  ALT=\"A+%2B+B+=+16\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Equation 2: (((0.5A + B = 13}}}\r<BR>\n" );
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document.write( "Solution:<BR>\n" );
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document.write( "Solve equation 1 for one of the variables. I will solve for B<BR>\n" );
document.write( "Equation 1: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+%2B+B+=+16 ALIGN=MIDDLE  ALT=\"A+%2B+B+=+16\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=B+=+16+-+A ALIGN=MIDDLE  ALT=\"B+=+16+-+A\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Now plug (16 - A) into equation 2 for B<BR>\n" );
document.write( "Equation 2: (((0.5A + B = 13}}}<BR>\n" );
document.write( "(((0.5A + (16 - A) = 13}}} Simplify<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0.5A+%2B+16+-+A+=+13 ALIGN=MIDDLE  ALT=\"0.5A+%2B+16+-+A+=+13\"   DISABLED_style= \"max-width:90%; height:auto;\" > Combine like terms<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-.05A+%2B+16+=+13 ALIGN=MIDDLE  ALT=\"-.05A+%2B+16+=+13\"   DISABLED_style= \"max-width:90%; height:auto;\" > Subtract 16 from both sides<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-0.5A+=+-3 ALIGN=MIDDLE  ALT=\"-0.5A+=+-3\"   DISABLED_style= \"max-width:90%; height:auto;\" > Divide both sides by -0.5<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28A+=+6%29 ALIGN=MIDDLE  ALT=\"highlight%28A+=+6%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Now find B by plugging 6 into equation 1 for A<BR>\n" );
document.write( "Equation 1: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+%2B+B+=+16 ALIGN=MIDDLE  ALT=\"A+%2B+B+=+16\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6+%2B+B+=+16 ALIGN=MIDDLE  ALT=\"6+%2B+B+=+16\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28B+=+10%29 ALIGN=MIDDLE  ALT=\"highlight%28B+=+10%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Check your answer:<BR>\n" );
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document.write( "Plug your values into equation 2 and see if it checks out.<BR>\n" );
document.write( "Equation 2: (((0.5A + B = 13}}}<BR>\n" );
document.write( "(((0.5*(6) + 10 = 13}}}<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3+%2B+10+=+13 ALIGN=MIDDLE  ALT=\"3+%2B+10+=+13\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%2813+=+13%29 ALIGN=MIDDLE  ALT=\"highlight%2813+=+13%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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