9514 1404 393
Answer:
84 adult tickets
Explanation:
Let 'a' represent the number of adult tickets sold. Then (135-a) is the number of child tickets sold, and total revenue is ...
5.70(135 -a) +9.40(a) = 1080.30
3.70a = 310.80 . . . . . . . . subtract 769.50 and simplify
a = 310.80/3.70 = 84
84 adult tickets were sold on Sunday.