The equation above can be used to model the population, in thousands, of a certain city t years after 2000. According to the model, the population is predicted to increase by 0.5% every n months. What is the value of n?

The correct answer is: 36

The given equation is

The growth factor is given by

Thus, we see that the growth is 0.5% every three years (as the denominator of t is 3).
According to the question, the population increases by 0.5 %every n months.
But we have found that the population increases by 0.5% in 3 years.
So, n= 3 years
Hence,  months.
The correct option is D)

Note:
We need to understand what each quantity given in the equation 
represents. For example, the population in year 2000 is 2,15,000. After 3 tears, that is, in year 2003, the population becomes  thousand which is 216075.