document.write( "Question 1159189: The count in a bacteria culture was 600 after 10 minutes and 2000 after 35 minutes. Assuming the count grows exponentially,\r
\n" ); document.write( "\n" ); document.write( "What was the initial size of the culture?
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\n" ); document.write( "\n" ); document.write( "Find the doubling period.
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\n" ); document.write( "\n" ); document.write( "Find the population after 120 minutes.
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\n" ); document.write( "\n" ); document.write( "When will the population reach 10000
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Algebra.Com's Answer #782276 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
The count in a bacteria culture was 600 after 10 minutes and 2000 after 35 minutes.
\n" ); document.write( " Assuming the count grows exponentially,
\n" ); document.write( "Using the form that a*b^x = y
\n" ); document.write( "x=10, y=600
\n" ); document.write( "\"a%2Ab%5E10+=+600\"
\n" ); document.write( "\"a+=+600%2Fb%5E10\"
\n" ); document.write( "x=35, y=2000
\n" ); document.write( "\"a%2Ab%5E35+=+2000\"
\n" ); document.write( "replace a with \"600%2Fb%5E10\"
\n" ); document.write( "\"%28600%2Fb%5E10%29%2Ab%5E35+=+2000\"
\n" ); document.write( "cancel b^10
\n" ); document.write( "\"600%2Ab%5E25+=+2000\"
\n" ); document.write( "\"b%5E25+=+2000%2F600\"
\n" ); document.write( "\"b%5E25+=+20%2F6\"
\n" ); document.write( "\"25%2Aln%28b%29+=+ln%283.333%29\"
\n" ); document.write( "ln(b) = ln(3.333)/25}}}
\n" ); document.write( "ln(b) = .048159
\n" ); document.write( "b = 1.049337
\n" ); document.write( "Find a
\n" ); document.write( "a = \"600%2F1.048337%5E10\"
\n" ); document.write( "a = \"600%2F1.6186\"
\n" ); document.write( "a = 370.7
\n" ); document.write( "The equation
\n" ); document.write( "\"y+=+370.7%2A1.049337%5Ex%29\"
\n" ); document.write( ":
\n" ); document.write( "What was the initial size of the culture?
\n" ); document.write( "x=0, therefore 370.7 is the initial amt
\n" ); document.write( ":
\n" ); document.write( "Find the doubling period.
\n" ); document.write( "\"1.049337%5Ex+=+2\"
\n" ); document.write( "x*ln(1.049337) = ln(2)
\n" ); document.write( "\"x+=+ln%282%29%2Fln%281.049337%29\"
\n" ); document.write( "x = 14.4 min
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\n" ); document.write( "Find the population after 120 minutes.
\n" ); document.write( "\"y+=+370.7%2A1.049337%5E120%29\"
\n" ); document.write( "y = 370.7*323.443
\n" ); document.write( "y = 119,900.5
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\n" ); document.write( "When will the population reach 10000
\n" ); document.write( "\"370.7%2A1.049337%5Ex+=+10000\"
\n" ); document.write( "\"1.049337%5Ex+=+10000%2F370.7\"
\n" ); document.write( "\"1.049337%5Ex+=+26.976\"
\n" ); document.write( "x*ln(1.049337) = ln(26.976)
\n" ); document.write( "\"x+=+ln%2826.976%29%2Fln%281.049337%29\"
\n" ); document.write( "x = 68.42 min
\n" ); document.write( ":
\n" ); document.write( "looks like this
\n" ); document.write( "\"+graph%28+300%2C+200%2C+-50%2C+150%2C+-20000%2C+100000%2C+370.7%2A1.049337%5Ex%29+\"
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