With a system of equations, it is found that there were 4,000 children tickets sold.
<h3>What is a system of equations?</h3>
A system of equations is when two or more variables are related, and equations are built to find the values of each variable.
For this problem, the variables are given by:
- Variable x: Number of children tickets sold.
- Variable y: Number of adult tickets sold.
From the matrices, and the data given, the equations are:
- x + y = 5000 -> y = 5000 - x.
Replacing the second equation into the first:
15x + 40(5000 - x) = 100000
25x = 100000
x = 100000/25
x = 4000.
There were 4,000 children tickets sold.
More can be learned about a system of equations at brainly.com/question/24342899
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