This is a systems of equations problem. To begin, we need to set up our equations.
If there was a total of 548 dollars collected, and adult tickets cost $6, and students tickets $4, this equation represents that situation.
6a + 4s = 548
The variable a stands for adult, and variable s for student. Now, if 12 more student tickets were sold than adults, this would represent that.
a + 12 = s
Now we can set it up as a systems of equations.
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Because s = a + 12, we can plug that in into the other equation.
6a + 4(a + 12) = 548
Distribute 4.
6a + 4a + 48 = 548
Combine like terms.
10a + 48 = 548
Subtract 48 from both sides.
10a = 500
Divide both sides by 10.
a = 50
Plug a into the original equation.
50 + 12 = s
Combine like terms.
62 = s
There were 62 student tickets and 50 adult tickets sold.