document.write( "Question 1140192: Question Help
\n" ); document.write( "The population of a colony of mosquitoes obeys the law of uninhibited growth. If there are 1000 mosquitoes initially and there are 1400 after 1​ day, what is the size of the colony after
\n" ); document.write( "3 ​days? How long is it until there are 70,000 ​mosquitoes?
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Algebra.Com's Answer #760716 by greenestamps(13200)\"\" \"About 
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\n" ); document.write( "There are good reasons in certain cases to use exponential growth using the natural base e. But in this simple example it greatly complicates the solution.

\n" ); document.write( "The population grew from 1000 to 1400 in 1 day; the daily growth factor is 1400/1000 = 1.4. So the equation for the number of mosquitoes after n days is

\n" ); document.write( "\"P%28n%29+=+1000%281.4%29%5En\"

\n" ); document.write( "(1) For the population after 3 days, evaluate the equation for n=3:
\n" ); document.write( "\"P%283%29+=+1000%281.4%29%5E3+=+2744\"

\n" ); document.write( "The population is about 2744 after 3 days.

\n" ); document.write( "(2) To find the number of days for the population to reach 70,000, set P=70000 and solve for n.

\n" ); document.write( "\"70000+=+1000%281.4%29%5En\"
\n" ); document.write( "\"70+=+1.4%5En\"
\n" ); document.write( "\"log%28%2870%29%29+=+n%2Alog%28%281.4%29%29\"
\n" ); document.write( "\"n+=+log%28%2870%29%29%2Flog%28%281.4%29%29\" = 12.626585 to several decimal places

\n" ); document.write( "It takes about 12.6 days for the population to reach 70,000.
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