In 1985, there was 285 cell phones subscribers in the small town of centerville.After 1985, the number of subscribers increased by 75% per year. How many cell phones subscribers were in centerville in 1994 ?
First we write a function that suits the problem. We have then: y = 285 * (1.75) ^ x Then, we see how many years there are in the requested period x = 1994-1985 = 9 We evaluate the function for x = 9 y = 285 * (1.75) ^ 9 y = 43871.98637 Round nearest whole number y = 43872 Answer: there were 43872 cell phones subscribers in centerville in 1994