document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=162723>Question 162723</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help. I am so lost.<BR>\n" );
document.write( "A cellular phone company offers a contract for which the cost C, in dollars, of t minutes of telephoning is given by C=0.25(t-500)+ 56.95, where it is assumed that t is greater than or equal to 500 minutes. What times will keep cost between $94.95 and $144.45?<BR>\n" );
document.write( "For the cost to be between $94.95 and $144.45, the telephoning time must be between ______ minutes and _________minutes.\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 #119943 by </B><A HREF=/tutors/aboutme.mpl?userid=nerdybill><B>nerdybill(7384)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=nerdybill><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=nerdybill><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=119943\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A cellular phone company offers a contract for which the cost C, in dollars, of t minutes of telephoning is given by C=0.25(t-500)+ 56.95, where it is assumed that t is greater than or equal to 500 minutes. What times will keep cost between $94.95 and $144.45?<BR>\n" );
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document.write( "The problem provides the formula for cost:<BR>\n" );
document.write( "C=0.25(t-500)+ 56.95<BR>\n" );
document.write( "where<BR>\n" );
document.write( "C is cost<BR>\n" );
document.write( "t is minutes<BR>\n" );
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document.write( "They want to know the \"minutes\" used if the cost is between $94.95 and $144.45<BR>\n" );
document.write( "So, plug each cost and solve for t.<BR>\n" );
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document.write( "Lower bound:<BR>\n" );
document.write( "C=0.25(t-500)+ 56.95<BR>\n" );
document.write( "94.95=0.25(t-500)+ 56.95<BR>\n" );
document.write( "94.95=0.25t - 125 + 56.95<BR>\n" );
document.write( "94.95=0.25t - 68.05<BR>\n" );
document.write( "163=0.25t<BR>\n" );
document.write( "652 minutes = t<BR>\n" );
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document.write( "Upper bound:<BR>\n" );
document.write( "C=0.25(t-500)+ 56.95<BR>\n" );
document.write( "144.45=0.25(t-500)+ 56.95<BR>\n" );
document.write( "144.45=0.25t - 125 + 56.95<BR>\n" );
document.write( "144.45=0.25t - 68.05<BR>\n" );
document.write( "212.5=0.25t<BR>\n" );
document.write( "850 minutes = t<BR>\n" );
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document.write( "For the cost to be between $94.95 and $144.45, the telephoning time must be between 652 minutes and 850 minutes.  </SPAN>\n" );
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