document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1140288>Question 1140288</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I don't know how to solve this word problem:<BR>\n" );
document.write( "The half life of carbon-14 is 5715 years. Prehistoric cave paintings were discovered in a cave in France. The paint contained 15% if the original carbon-14. Estimate the age of paintings.<BR>\n" );
document.write( "I'm supposed to be using one of these formulas:<BR>\n" );
document.write( "y=k(a)^x<BR>\n" );
document.write( "At=Ao(1+r)^t<BR>\n" );
document.write( "At=Ao(e)^rt<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #760781 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39623)</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=760781\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You can select the form of the model that you want.\r<BR>\n" );
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document.write( "Halflife given as  5715 years\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=A%5Bo%5De%5E%28-kt%29 ALIGN=MIDDLE  ALT=\"A=A%5Bo%5De%5E%28-kt%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F2=1%2Ae%5E%28-kt%29 ALIGN=MIDDLE  ALT=\"1%2F2=1%2Ae%5E%28-kt%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%281%2F2%29=-kt ALIGN=MIDDLE  ALT=\"ln%281%2F2%29=-kt\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%282%29=kt ALIGN=MIDDLE  ALT=\"ln%282%29=kt\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=ln%282%29%2Ft ALIGN=MIDDLE  ALT=\"k=ln%282%29%2Ft\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=ln%282%29%2F5715 ALIGN=MIDDLE  ALT=\"k=ln%282%29%2F5715\"   DISABLED_style= \"max-width:90%; height:auto;\" >------------<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=0.0001213 ALIGN=MIDDLE  ALT=\"k=0.0001213\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "model can then be <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight_green%28A=A%5Bo%5De%5E%28-0.0001213t%29%29 ALIGN=MIDDLE  ALT=\"highlight_green%28A=A%5Bo%5De%5E%28-0.0001213t%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "The paint contained 15% if the original carbon-14. Estimate the age of paintings.<BR>\n" );
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document.write( "This means  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0.15=1%2Ae%5E%28-0.0001213t%29 ALIGN=MIDDLE  ALT=\"0.15=1%2Ae%5E%28-0.0001213t%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, and similar to some of the steps shown above, you can solve for t. </SPAN>\n" );
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