document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1164695>Question 1164695</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A well drilling company offers two plans. Under the \"pay as you go\" plan, they charge $300 plus $5 per foot for a well of any depth. Under the \"guaranteed-water\" plan, they charch a flat fee of $8000 for a well that is guarenteed to preovide adaquate water for a household. For what depths would save a customer money to use the \"pay as you go\" plan?<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 #789106 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=789106\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the pay as you go plan charges 300 dollars plus 5 dollars a foot.<BR>\n" );
document.write( "the guaranteed water plan charges a flat fee of 8000 dollars.\r<BR>\n" );
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document.write( "let x equal the number of feet of depth that needs to be drilled to get adequate water for a household.\r<BR>\n" );
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document.write( "the formula for pay as you go becomes y1 = 300 + 5x.<BR>\n" );
document.write( "the guaranteed water plan becomes y2 = 8000.\r<BR>\n" );
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document.write( "the pay as you go plan will be cheaper when y1 < y2.<BR>\n" );
document.write( "this occurs when 300 + 5x < 8000<BR>\n" );
document.write( "subtract 300 from both sides of this inequality to get:<BR>\n" );
document.write( "5x < 7700<BR>\n" );
document.write( "divide both sides of this inequality by 5 to get:<BR>\n" );
document.write( "x < 1540\r<BR>\n" );
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document.write( "the pay as you go plan will be cheaper than the guaranteed water plan when the number of feet of depth that has to be drilled is less than 1540.\r<BR>\n" );
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document.write( "when the depth is 1539, the pay as you go plan is 300 + 5 * 1539 = 7995.<BR>\n" );
document.write( "when the depth is 1540, the pay as you go plan is 300 + 5 * 1540 = 8000.<BR>\n" );
document.write( "when the depth is 1541, the pay as you go plan is 300 + 5 * 1541 = 8005.\r<BR>\n" );
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document.write( "you can see that the pay as you go plan is cheaper when the depth is less than 1540.\r<BR>\n" );
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