Answer: The number of $12 tickets and $15 sold are 120 and 180 respectively.
Explanation:
The given equation is:
12x + 15y = 4140 .....(1)
Where,
x stands for $12 tickets and y stands for $15 tickets
According to the question:
x + y = 300 ....(2)
Now solving equation 1 and 2.
From equation 2:
x = 300 - y
Now putting this expression in equation 1.
12x + 15y = 4140
12(300 - y) + 15y = 4140
3600 - 12y + 15y = 4140
3600 + 3y = 4140
3y = 4140 - 3600
3y = 540
y = 180
And,
x = 300 - y = 300 - 180 = 120
The number of $12 tickets sold = x = 120
The number of $15 tickets sold = y = 180
Thus, the number of $12 tickets and $15 sold are 120 and 180 respectively.