Answer:
75 student tickets and 10 chaperone tickets
Explanation:
First find out how many groups there are total by dividing 85 by 1 group total of 17 (15 students 2 chaperones).
85 / 17 = 5
Since you now know there are five groups of 15 students and 2 chaperones all you have to do is multiply 5 time 15 students and 5 times 2 chaperones.
15 x 5 = 75 for students
5 x 2 = 10 for chaperones