document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=80427>Question 80427</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Can someone help me please?\r<BR>\n" );
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document.write( "The average number of diners in a restaurant can be modeled with the function <BR>\n" );
document.write( "D(t)= -2t^2+20t+15 , where t is the number of hours after 8:00 A.M. At what time is the number of diners at its maximum?\r<BR>\n" );
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document.write( "thanks so much! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #57706 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=57706\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The average number of diners in a restaurant can be modeled with the function <BR>\n" );
document.write( "D(t)= -2t^2+20t+15 , where t is the number of hours after 8:00 A.M. At what time is the number of diners at its maximum?\r<BR>\n" );
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document.write( "You have a quadratic with a=-2 , b=20<BR>\n" );
document.write( "Max occurs when t=-b/2a = -20/(2*-2)= 5 hurs<BR>\n" );
document.write( "5hrs after 8:00AM is 1:PM<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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