Let's denote the number of adults as \( A \) and the number of children as \( C \).
We have two equations based on the information provided:
-
The total number of attendees:
\[ A + C = 500 \] -
The total revenue from admissions:
\[ 10A + 5C = 3500 \]
Now we can solve these equations step by step.
Step 1: Solve for \( C \) in terms of \( A \)
From the first equation, we can express \( C \) in terms of \( A \): \[ C = 500 - A \]
Step 2: Substitute \( C \) in the second equation
Now we substitute \( C \) in the second equation: \[ 10A + 5(500 - A) = 3500 \]
Distribute the \( 5 \): \[ 10A + 2500 - 5A = 3500 \]
Combine like terms: \[ 5A + 2500 = 3500 \]
Step 3: Isolate \( A \)
Subtract \( 2500 \) from both sides: \[ 5A = 1000 \]
Now divide by \( 5 \): \[ A = 200 \]
Step 4: Calculate \( C \)
Now that we have \( A \), we can find \( C \): \[ C = 500 - A = 500 - 200 = 300 \]
Summary
Thus, the number of adults and children needed to attend to reach the goal of $3,500 is:
- 200 adults
- 300 children
Final answer: 200 adults; 300 children.