document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=635638>Question 635638</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve the following equation:\r<BR>\n" );
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document.write( "220 X 4^(-0.02t) = 1540 </SPAN>\n" );
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document.write( "This 220 X 4^(-0.02t) = 1540<BR>\n" );
document.write( "We first divide by 220<BR>\n" );
document.write( "4^(-0.02t) = 7<BR>\n" );
document.write( "Rewritten as log we get:<BR>\n" );
document.write( "Log base 4 7=-0.02t<BR>\n" );
document.write( "Divide by -.02<BR>\n" );
document.write( "(Log base 4 350)/-0.02 = t<BR>\n" );
document.write( "Using scientific calculator we get:<BR>\n" );
document.write( "t=-70.184 (rounded off)<BR>\n" );
document.write( "Make sense?<BR>\n" );
document.write( "RJ<BR>\n" );
document.write( "www.math-unlock.com </SPAN>\n" );
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