Answer: the number of children tickets sold 265
the number of adult tickets sold 77
Step-by-step explanation:
Let x represent the number of children tickets sold.
Let y represent the number of adult tickets sold.
They charge $5 per ticket for a child and $12 per ticket for an adult. They were sold for a total of $2250. This means that
5x + 12y = 2250 - - - - - - - - - -1
The total number of tickets sold is 342. This means that
x + y = 342
Substituting x = 342 - y into equation 1, it becomes
5(342 - y) + 12y = 2250
1710 - 5y + 12y = 2250
- 5y + 12y = 2250 - 1710
7y = 540
y = 540/7 = 77
x = 342 - y = 342 - 77
x = 265