Answer:
Let's call the number of $5 child tickets sold "x".
According to the problem, the number of $adult tickets was 14 less than twice the number of child tickets, so the number of $adult tickets sold can be represented as 2x - 14.
The total revenue from ticket sales was $728, so we can set up an equation:
5x + 20(2x - 14) = 728
Expanding the second term on the left side of the equation:
5x + 40x - 280 = 728
Combining like terms:
45x = 1008
Dividing both sides of the equation by 45:
x = 22.4
So the number of child tickets sold was 22 and the number of adult tickets sold was 2 * 22 - 14 = 36.