Question

A population has size 25 at time t = 0, with t measured in years. (a) if the population decreases by 4 people per year, find a function for the population size, p, at time t. enter your answer as an equation with p on the left side, and an expression involving t on the right

Answer 1

First we define the variables:
 p = population
 t: time in years
 The equation that best fits this problem is a linear equation of the form:
 p = -4t + 25
 Note that for t = 0 the value of p is 25, which represents the initial population.
 Answer: 
 a function for the population size, p, at time t is: 
 p = -4t + 25