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math for the expanding population
Read, Dwight ANTHRO (Read@ANTHRO.SSCNET.UCLA.EDU)
Mon, 2 Jan 1995 15:22:00 PST
Bonnie Blackwell provides the basic demographic equation for a growing
population. The following may be a useful addition to what she presented:
Let D be the number of years for a populaiton to double in size,
let r be the net growth rate (expressed as a proportion).
Then D = ln2/r, where ln2 is the natural log of 2.
ln2 = (approximtely) 0.695
So with a net growth rate of 2.78% the doubling time is 0.695/.0278= 25 years.
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D. Read
READ@ANTHRO.SSCNET.UCLA.EDU
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