Question

Kelly opened a savings account for college with $2000 and plans to add $50 every month. The total amount of money in her account can

be given by the function f(z) = 2000+50z, where x represents the number of months since she opened the account. The graph that
represents her account is given.
What would be the difference between the mathematical domain of the function rule and the reasonable domain that represents her
situation?

Answer 1

The mathematical domain would be all real numbers.

However, the reasonable domain would be non-negative integers, since the number of months must be a whole number or zero.