document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=747347>Question 747347</A>: <I><SPAN STYLE=\"word-break: break-all;\"> At the beginning of an experiment, a scientist has 244 grams of radioactive goo. After 240 minutes, her sample has decayed to 3.8125 grams. what is the half life of goo in minutes? Find a formula for G(t), the amount of goo remaining at time t. How many grams of goo will remain after 47 minutes. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #454856 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=454856\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> At the beginning of an experiment, a scientist has 244 grams of radioactive goo. After 240 minutes, her sample has decayed to 3.8125 grams. what is the half life of goo in minutes?<BR>\n" );
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document.write( "A(t) = Ao*(1/2)^(t)<BR>\n" );
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document.write( "3.8125 = 244*(1/2)^(240/k)<BR>\n" );
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document.write( "0.0157 = (1/2)^(240/k)<BR>\n" );
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document.write( "(240/k) = log(0.0157)/log(0.5) = 5.9953<BR>\n" );
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document.write( "k = 240/5.9953<BR>\n" );
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document.write( "k = 6 minutes<BR>\n" );
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document.write( " Find a formula for G(t), the amount of goo remaining at time t. How many grams of goo will remain after 47 minutes.<BR>\n" );
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document.write( "A(47) = 244*(1/2)^(47/6)<BR>\n" );
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document.write( "A(47) = 244*(1/2)^7.833<BR>\n" );
document.write( "A(47) = 1.0698 grams<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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document.write( " </SPAN>\n" );
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