Question 90069
The U.S. population in 1990 was approximately 250 million, and the average growth rate for the past 30 years gives a doubling time of 66 years. The above formula for theUnited States then becomes 
P (in millions) =[ 250 * 2^[( y-1990)/66]]
The question is : What will the population of the United States be in 2025 if thisgrowth rate continues?
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P(2025) = [250*2^[(2025-1990)/66]
P(2025) = [250*2^(35/66)]
P(2025) = [250*1.444232517]
P(2025) = [361.058... million]
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Cheers,
Stan H.