document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=308886>Question 308886</A>: <I><SPAN STYLE=\"word-break: break-all;\"> assume that i sell 66 sandwiches when selling them for $1. if i lose 5 customers each time i raise the price $.25, what is the price that will produce the higherst amount of sales? what is the amount of money i will bring in? solve using quadratics. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #220893 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=220893\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> assume that i sell 66 sandwiches when selling them for $1. if i lose 5 customers each time i raise the price $.25, what is the price that will<BR>\n" );
document.write( " produce the highest amount of sales?<BR>\n" );
document.write( " what is the amount of money i will bring in? solve using quadratics.<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Let x = no. of .25 increases & no. of 5 customer decreases<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Revenue = price * no. sold<BR>\n" );
document.write( "R(x) = (1 + .25x)(66 - 5x)<BR>\n" );
document.write( "FOIL<BR>\n" );
document.write( "R(x) = 66 - 5x + 16.5x - 1.25x^2<BR>\n" );
document.write( "R(x) = 66 + 11.5x - 1.25x^2<BR>\n" );
document.write( "A quadratic equation<BR>\n" );
document.write( "y = -1.25x^2 + 11.5x + 66<BR>\n" );
document.write( "Find the axis of symmetry; x = -b/(2a), a=-1.25, b=+11.5<BR>\n" );
document.write( "x = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-11.5%29%2F%282%2A-1.25%29 ALIGN=MIDDLE  ALT=\"%28-11.5%29%2F%282%2A-1.25%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "x = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-11.5%29%2F%28-2.5%29 ALIGN=MIDDLE  ALT=\"%28-11.5%29%2F%28-2.5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "x = 4.6 ~ 5, have to have an integer<BR>\n" );
document.write( "Price for max revenue: 1 + 5(.25) = $2.25<BR>\n" );
document.write( "No. sold: 66 - 5(5) = 41 sold<BR>\n" );
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document.write( "Find the max revenue; substitute 5 for x in the quadratic equation<BR>\n" );
document.write( "R(x) = -1.25(5^2) + 11.5(5) + 66<BR>\n" );
document.write( "R(x) = -1.25(25) + 57.5 + 66<BR>\n" );
document.write( "R(x) = -32.25 + 57.5 + 66<BR>\n" );
document.write( "R(x) = $92.25<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Check: Price * no. sold<BR>\n" );
document.write( "2.25 * 41  = 92.25 max sales<BR>\n" );
document.write( " </SPAN>\n" );
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