Answer:
advance tickets cost $20 each & same-day tickets cost $35 each
Explanation:
Let cost of advanced ticket be x and cost of same-day ticket be y. Now we can write 2 equations and solve them simultaneously.
"The combined cost of one advance ticket and one same-day ticket is $55":

and
"...40 advance tickets and 15 same-day tickets were sold. The total amount paid for the tickets was $1325":

We solve for x in the first equation to get x = 55 - y and substitute this into 2nd equation and solve for y:

Now plugging in y = 35 into the first equation, we can solve for x:

Hence, advance tickets cost $20 each & same-day tickets cost $35 each