The equation is
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, and the population in 2020 is 826.
We find the rate of increase using the formula
amount of change/original amount.
Using the first two data points, we have (515-500)/500 = 15/500 = 0.03. This is r.
b is the initial value, which in this case is 500.
This gives us the equation
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The first year, 2003, will be considered year 0, since it is before any changes took place. This means 2020 will be year (2020-2003) = 17:
