document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1161507>Question 1161507</A>: <I><SPAN STYLE=\"word-break: break-all;\"> the number of people, P, at a playground after x min is given by P = x^3 + 4x + 20. The instantaneous rate of change of the number of people at the playground after 1 min is approximately \r<BR>\n" );
document.write( "\n" );
document.write( "a) 4 people/min<BR>\n" );
document.write( "b) 5 people/min<BR>\n" );
document.write( "c) 6 people/min<BR>\n" );
document.write( "d) 7 people/min </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #785095 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=785095\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "Instantaneous rate of change after 1 minute = derivative of function evaluated at t=1.<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P+=+x%5E3%2B4x%2B20 ALIGN=MIDDLE  ALT=\"P+=+x%5E3%2B4x%2B20\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=dP%2Fdx+=+3x%5E2%2B4 ALIGN=MIDDLE  ALT=\"dP%2Fdx+=+3x%5E2%2B4\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3%281%5E2%29%2B4+=+3%2B4+=+7 ALIGN=MIDDLE  ALT=\"3%281%5E2%29%2B4+=+3%2B4+=+7\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );