document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1135477>Question 1135477</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A video rental service has 1100 subscribers, each of whom pays $12 per month. On the basis of a survey, the company believes that for each decrease of $0.20 in the monthly rate, it could obtain 50 additional subscribers. At what rate will the maximum revenue be obtained, and how many subscribers will there be at that rate? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #753081 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=753081\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> x=number of -$0.20 per +50 more subscribers<BR>\n" );
document.write( "(1100+50x)(12-0.20x) has to be maximized.  This is 13200+380x-10x^2 and the vertex x value is at -b/2a or 380/20 or 19<BR>\n" );
document.write( "This would be 19*50 more subscribers or 2050 total<BR>\n" );
document.write( "They would each pay $3.80 less or $8.20 per month<BR>\n" );
document.write( "The revenue would be $16810 a month.<BR>\n" );
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