document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1035108>Question 1035108</A>: <I><SPAN STYLE=\"word-break: break-all;\"> between the start of 2005 and the end of 2009, the number of Facebook users can be modelled by the exponent equation u=0.43*(3.17)^t, where u is the number of users in millions nd t is the number of years since 2004 (1<=t<6)\r<BR>\n" );
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document.write( "How do I find the year in which the exponential model predicts that the number of users would first reach 200 million?   (I know that the 1 year since 2004, the number of Facebook users is 1.4 million)\r<BR>\n" );
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document.write( "Thanks for your help </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #688614 by </B><A HREF=/tutors/aboutme.mpl?userid=jorel1380><B>jorel1380(3719)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jorel1380><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=jorel1380><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=688614\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If u is the number of Facebook users in millions, and u=.43*(3.17)^t, where t is the number of years since 2004, then:<BR>\n" );
document.write( "200=.43*(3.17)^t<BR>\n" );
document.write( "465.12=3.17^t<BR>\n" );
document.write( "log 465.12=log 3.17^t<BR>\n" );
document.write( "log 465.12=t log 3.17<BR>\n" );
document.write( "t=log 465.12/log 3.17=5.32385131974 years after 2004 that the amount of Facebook users will reach 200 million. &#9786;&#9786;&#9786;&#9786; </SPAN>\n" );
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