document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1021133>Question 1021133</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A scientist begins an experiment with a petri dish containing a culture of bacteria cells and records the cell growth every hour. At 1 hour, the bacteria had grown to 880 cells, and at 2 hours, had grown to 3,520 cells. Which function can be used to represent the relationship between the number of bacteria cells, y, and the time in hours, x?\r<BR>\n" );
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document.write( "y  = 4 x<BR>\n" );
document.write( "y  = 220(4) x<BR>\n" );
document.write( "y  = 880(4) x<BR>\n" );
document.write( "y  = 880(0.25) x </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #636886 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39620)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=636886\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The choices look strange.  Try starting with a general model <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=p%2Ae%5E%28kx%29 ALIGN=MIDDLE  ALT=\"y=p%2Ae%5E%28kx%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.  Two points are  (1,880) and (2,3520).  You might instead try a general model <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=p%2A%281%2Br%29%5Ex ALIGN=MIDDLE  ALT=\"y=p%2A%281%2Br%29%5Ex\"   DISABLED_style= \"max-width:90%; height:auto;\" > in which the rate of growth per hour is r, as a decimal value.  This form of the model might be better for the kinds of choices you want to use.\r<BR>\n" );
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document.write( "One point gives an equation  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=p%2A%281%2Br%29%5E1=880 ALIGN=MIDDLE  ALT=\"p%2A%281%2Br%29%5E1=880\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=p%281%2Br%29=880 ALIGN=MIDDLE  ALT=\"p%281%2Br%29=880\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and the other point gives  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=p%2A%281%2Br%29%5E2=3520 ALIGN=MIDDLE  ALT=\"p%2A%281%2Br%29%5E2=3520\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "First one gives <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=p=880%2F%281%2Br%29 ALIGN=MIDDLE  ALT=\"p=880%2F%281%2Br%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, and substituted into the second equation gives  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%288%2F%281%2Br%29%29%281%2Br%29%5E2=3520 ALIGN=MIDDLE  ALT=\"%288%2F%281%2Br%29%29%281%2Br%29%5E2=3520\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "simplifiable as  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=8%281%2Br%29=3520 ALIGN=MIDDLE  ALT=\"8%281%2Br%29=3520\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "allowing you to find r.<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2Br=3520%2F8 ALIGN=MIDDLE  ALT=\"1%2Br=3520%2F8\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r=3520%2F8-1 ALIGN=MIDDLE  ALT=\"r=3520%2F8-1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r=439 ALIGN=MIDDLE  ALT=\"r=439\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Using this in the first equation <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=p%28440%29=880 ALIGN=MIDDLE  ALT=\"p%28440%29=880\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=p=2 ALIGN=MIDDLE  ALT=\"p=2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Putting these into the model from the general form makes <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=2%2A%281%2B439%29%5Ex ALIGN=MIDDLE  ALT=\"y=2%2A%281%2B439%29%5Ex\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Simpliable to <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=2%2A440%5Ex ALIGN=MIDDLE  ALT=\"y=2%2A440%5Ex\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28y=880%5Ex%29 ALIGN=MIDDLE  ALT=\"highlight%28y=880%5Ex%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Still not the same as any of the choices you have. </SPAN>\n" );
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