Answer:
You need to sell 39 Student tickets minimum to be able to cover the cost over all.
Explanation:
If they sell 65 adult tickets, then you have to do 65 x 10.50 = $682.5
with that in mind you will take 308 + 682.5 because that equals 990.5 that would be the minimum amount but you would need to to take 39 x 8 to get 312 because 38 x 8 is 304 so that isn't enough.