Answer:
The maximum total cost for tickets is $320 + $160 = $480.
Explanation:
The maximum number of people that can go on the field trip is 100, so the maximum number of students is 100 - (100/5) = 80 students.
The maximum number of adult chaperones is 1 adult chaperone for every 4 students, so the maximum number of chaperones is 80/4 = 20 chaperones.
The total cost for student tickets is $4 x 80 = $320.
The total cost for adult chaperone tickets is $8 x 20 = $160.
The maximum total cost for tickets is $320 + $160 = $480.