Answer:
You will need to use your cost per ticket and divide it into 5000
If there is a structure price ie) adult child or season etc you can graph the rate of increase price from eg) £20-£15 = $5 and decide that more adult seats are purchased at 1:4 ratio or 2:3 ratio and for 1:4 ratio you first divide 4000/20 and then any remainder add to the division of child seats divide 1000/15 and use remainder or count back one seat for adult until maximum seats are filled wth 5000 used.
Explanation:
Showing a rate of increase =m
Showing a number of people = p
Showing a number of seats = x