The current population of smyrna, maine, is 380 and grows at a rate of 3% per year. which equation could be used to determine how many years it will take for the population to reach 420 people?

The number of people after n years is calculated through the equation,
                            An = (Ao)(1 + r)^n
where An is the population after n years, Ao is the initial population and r is the rate. Substituting the known values,
                           420 = (380)(1 + 0.03)^n
The answer is letter A. 

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