Answer:
f(x) = 60 + 15n
Step-by-step explanation:
if the start off amount is 60, so we can simply start it with 60 + ...
If she gets 15 for each customer, and the amount of customers is equal to n, then this can be written by 15n ( 12 * n )
Simply put these two parts together:
60 + 15n
So in a function:
f(x) = 60 + 15n