SOLUTION: Suppose there are 350 million people in the US. If the annual birth rate is 2.3% and the annual death rate is 1.9%, what is the relative annual growth rate (r) of the US Population

Algebra ->  Rational-functions -> SOLUTION: Suppose there are 350 million people in the US. If the annual birth rate is 2.3% and the annual death rate is 1.9%, what is the relative annual growth rate (r) of the US Population      Log On


   

Question 1194834: Suppose there are 350 million people in the US. If the annual birth rate is 2.3% and the annual death rate is 1.9%, what is the relative annual growth rate (r) of the US Population?
a) What will the projected US Population be in 2042 based on an exponential growth model (base e)? Give the model and explain what each part represents.

b) What will the projected US Population be in 2050?

c) What will the projected US Population be in 2100?

d) What would happen if birth and death rates were reversed? Clearly explain what type of model this becomes and how the graph changes.
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
the annual birth rate is 2.3%.
the annual death rate is 1.9%.
the net growth rate per year is (2.3 - 1.9) = .4%.
the net growth factor per year is 1.004

the exponential growth model is y = a * b ^ x
a is the base population = 350
b is the annual growth factor = 1.004
x is the number of years.
the exponential growth formula becomes y = 350 * 1.004 ^ x

the graph of this equation is shown below:



the excel spreadsheet that supports the logic is shown below:



check it out.
see if it makes sense to you.
let me know if you have any questions.
theo