document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1191512>Question 1191512</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A laptop computer is purchased for $5000 . Each year, its value is 70%  of its value the year before. After how many years will the laptop computer be worth 800 or less? <BR>\n" );
document.write( "Write the smallest possible whole number answer. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #823332 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=823332\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> P=$5000(0.70)^t, where t is number of years. so if t=0, at the beginning, it is worth $5000, and it is worth $3500 the first year.<BR>\n" );
document.write( "800=5000(0.70)^t<BR>\n" );
document.write( "divide by 5000<BR>\n" );
document.write( "0.16=0.70^t<BR>\n" );
document.write( "log (0.16)=t log (0.70)<BR>\n" );
document.write( "t=log 0.16/log 0.70=5.14 years<BR>\n" );
document.write( "so it will be at 6 or more years<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );