Answer: 74 adult tickets were sold on Wednesday.
Step-by-step explanation:
Let x represent the number of child admission tickets sold on Wednesday.
Let y represent the number of adult admission tickets sold on Wednesday.
On Wednesday, 128 tickets were sold. It means that
x + y = 128
At the movie theatre, child admission is $6.40 and adult admission is $9.70. The total ticket sales on Wednesday was $1063.40. It means that
6.4x + 9.7y = 1063.4- - - - - - - - - - 1
Substituting x = 128 - y into equation 1, it becomes
6.4(128 - y) + 9.7y = 1063.4
819.2 - 6.4y + 9.7y = 1063.4
- 6.4y + 9.7y = 1063.4 - 819.2
3.3y = 244.2
y = 244.2/3.3
y = 74
x = 128 - y = 128 - 74
x = 54
