Modeling with Trigonometric Functions · Exercise 42

Create a function modeling the described behavior. Then, calculate the desired result using a calculator.

Whitefish populations are currently at 500 in a lake. The population naturally oscillates above and below by 25 each year. If humans overfish, taking 4% of the population every year, in how many years will the lake first have fewer than 200 whitefish?

Its source prints no answer for this problem, so there's nothing to check against.

OpenStax, Precalculus 2e · §7.6 Modeling with Trigonometric Functions · Exercise 42