Answer:
f(x) = -1.25x + 64 I hope this helps :)
Step-by-step explanation:
total amount of money: $80
He spent $16 for the entrance of the fair and food.
80-(4+12) = 64
After that you subtract $1.25 per ride = -1.25x
Then it gives the function:
f(x) = -1.25x + 64