SOLUTION: I need help, 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 formula for the U.S

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Question 41499This question is from textbook Beginning Algebra
: I need help, 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 formula for the U.S. is
p(in millions)= 250 x 2^(y-1990)/66

What will the population of the United States be in 2025 if this growth rate continues?
I get to the point of being able to substitute y for 2025 but when I subtract 2025-1990 and then divide by 66 I get .9848484848 and so on. I'm not sure what to do at this point. Can you help me figure this out. This question is from textbook Beginning Algebra

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
The formula for the U.S. is
p(in millions)= 250 x 2^(y-1990)/66

What will the population of the United States be in 2025 if this growth rate continues?

P ( in millions) = (250)2^(2025-1990)/66
P = (250)2^(35/66)
P = (250)2^0.53030303...
P = (250)1.44423252
P (in millions)= 361.058...
Cheers,
Stan H.