At the movie theater, children admissions is $5.20 and adults admission are $9.00. on friday, twice as many adult tickets as child tickets were sold. for a total sales of $556.80. how many children were sold that day.

24 child tickets

Step-by-step explanation:

Let x be the number of child tickets sold on Friday.

On Friday, twice as many adult tickets as child tickets were sold, then the number of adult tickets sold is 2x.

Children admissions is $5.20, then x child tickets cost $5,20x and adults admission are $9.00, so 2x adult tickets cost $9.00·2x. In total, x child tickets and 2x adult tickets cost

The total sales are $556.80, so

Therefore, 24 child tickets and 48 adult tickets were sold.

47 - 90 = 43

43 - 180 = x

x = 137