Answer: 33 child tickets were sold that day.
Step-by-step explanation:
Let x represent the number of child tickets that were sold on Thursday.
Let y represent the number of adult tickets that were sold on Thursday.
On Thursday, three times as many adult tickets as child tickets were sold. This means that
y = 3x
At the movie theatre, child admission is $5.60 and adult admission is $8.90. Total sales made on Thursday was $1065.90. This means that
5.6x + 8.9y = 1065.9 - - - - - - -- - -1
Substituting y = 3x into equation 1, it becomes
5.6x + 8.9 × 3x = 1065.9
5.6x + 26.7x = 1065.9
32.3x = 1065.9
x = 1065.9/32.3
x = 33
y = 3x = 3 × 33
y = 99
