document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=224325>Question 224325</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hello, me and my friend are working on this problem and we got two answers on our calculators. It's weird because we both kept getting the same two answers. Every other time we typed it in our answer would change. Here's the problem:\r<BR>\n" );
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document.write( "The traffic flow at a particular intersection is modeled by the function f defined by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+f%28t%29+=+25+%2B+6cos%28t%2F3%29+ ALIGN=MIDDLE  ALT=\"+f%28t%29+=+25+%2B+6cos%28t%2F3%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > for <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+0+%3Cor+equal+to+t+%3Cor+equal+to+120+ ALIGN=MIDDLE  ALT=\"+0+%3Cor+equal+to+t+%3Cor+equal+to+120+\"   DISABLED_style= \"max-width:90%; height:auto;\" > What is the average rate of change of the traffic flow over the time interval 30 <or equal to t <or equal to 40.\r<BR>\n" );
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document.write( "we set it up as:\r<BR>\n" );
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document.write( "the change in y/ the change in t = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%2825+%2B+6cos%2840%2F3%29+-+25+%2B+6cos%2830%2F3%29%29%2F+%2840+-+30%29+ ALIGN=MIDDLE  ALT=\"+%2825+%2B+6cos%2840%2F3%29+-+25+%2B+6cos%2830%2F3%29%29%2F+%2840+-+30%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "In the end our answers were 3.817 and -.0714299 \r<BR>\n" );
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document.write( "We have no clue what is right. Can you please help? Thanks in advance. =) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #167601 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=167601\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Do you mean the interval t=30 to t=40? That's what it appears to be.<BR>\n" );
document.write( "The term<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6cos%2830%2F3%29%29 ALIGN=MIDDLE  ALT=\"6cos%2830%2F3%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > should be negative.<BR>\n" );
document.write( "The 25's in the NUM cancel.<BR>\n" );
document.write( "--> 0.6(cos(40/3) - cos(10))<BR>\n" );
document.write( "= 0.6*-0.11762...<BR>\n" );
document.write( "= ~ - 0.0070577...\r<BR>\n" );
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document.write( " </SPAN>\n" );
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