Answer:
![5.10 X +9.00 Y = 831.60](https://img.qammunity.org/2021/formulas/mathematics/college/k4jnkbuumnfkwj7g2e5fsyktii69twrwzl.png)
We also know that for Wedneday we have two times tickets for adults compared to child so we have
![Y =2x](https://img.qammunity.org/2021/formulas/mathematics/college/v5vjctrzfy7jmwh3qrxy27h8k5kbtwqov8.png)
And using this condition we have:
![5.10 X + 18 X = 831.60](https://img.qammunity.org/2021/formulas/mathematics/college/c8osd7umtyn1whebkxs9ne8wtr948bk889.png)
And solving for X we got:
![X= (831.60)/(23.1)=36](https://img.qammunity.org/2021/formulas/mathematics/college/xyykg0j9w2pleet91kb7uyxujtczzyxvus.png)
So then the number of tickets sold for child are 36
Explanation:
For this problem we can set upt the following notation
X = number of tickets for child
Y= number of tickets for adults
And we know that the total revenue for Wednesday was 831.60. So then we can set up the following equation for the total revenue
![5.10 X +9.00 Y = 831.60](https://img.qammunity.org/2021/formulas/mathematics/college/k4jnkbuumnfkwj7g2e5fsyktii69twrwzl.png)
We also know that for Wedneday we have two times tickets for adults compared to child so we have
![Y =2x](https://img.qammunity.org/2021/formulas/mathematics/college/v5vjctrzfy7jmwh3qrxy27h8k5kbtwqov8.png)
And using this condition we have:
![5.10 X + 18 X = 831.60](https://img.qammunity.org/2021/formulas/mathematics/college/c8osd7umtyn1whebkxs9ne8wtr948bk889.png)
And solving for X we got:
![X= (831.60)/(23.1)=36](https://img.qammunity.org/2021/formulas/mathematics/college/xyykg0j9w2pleet91kb7uyxujtczzyxvus.png)
So then the number of tickets sold for child are 36