document.write( "Question 862226: The number of bacteria increased exponentially. At first there were 300. Six hours later there were 900. How many bacteria will there be in twelve hours?\r
\n" ); document.write( "\n" ); document.write( "This is what I did, solve for k? I got k= .18 by using this formula, 900=300e^k(6)\r
\n" ); document.write( "\n" ); document.write( "I am having trouble solving this. I get 2601 the solutions manual has 2700.
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Algebra.Com's Answer #519584 by josgarithmetic(39620)\"\" \"About 
You can put this solution on YOUR website!
Your model is ... not bad. Try this: \"900=300e%5E%28k%2A6%29\".\r
\n" ); document.write( "\n" ); document.write( "Simplify and solve for k.
\n" ); document.write( "\"3=e%5E%28k%2A6%29\"
\n" ); document.write( "\"ln%283%29=ln%28e%5E%286k%29%29\"
\n" ); document.write( "\"ln%283%29=6k%2A1\"
\n" ); document.write( "\"highlight_green%28k=%281%2F6%29ln%283%29%29\"
\n" ); document.write( "\"highlight%28k=0.183%29\"\r
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\n" ); document.write( "\n" ); document.write( "Now, let t=12 hours, and find the bacteria count.
\n" ); document.write( "\"C=300%2Ae%5E%280.183%2A12%29\"
\n" ); document.write( "\"C=300%2A9\"
\n" ); document.write( "\"highlight%28C=2700%29\".\r
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\n" ); document.write( "\n" ); document.write( "Notice that my solution simply used three significant figures while yours used two significant figures in the k value. That is why you found C=2601.
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