Question

The population of Canyon Edge is 210,000, and the rate of population growth is 12.5%.

Answer 1

For this case we have a function of the form:
 $y = A * (b) ^ x$
 Where,
 A: initial population
 b: growth rate
 x: number of years.
 We then have the following function:
 $y = 210000 * (1,125) ^ x$
 For x = 4 years we have:
 $y = 210000 * (1,125) ^ 4 y = 336379$
 Answer:
 the formula for exponential growth is:
 y = 210000 * (1,125) ^ x
 The population of Canyon Edge after 4 years is:
 y = 336379