John C. answered 11/13/20
The Problem Solver
One advance ticket plus one same-day ticket cost $65.
15 advance tickets plus 15 same-day tickets cost 15x$65=$975.
Add 20 same-day tickets and the total gate is $1675.
So 20 same-day tickets cost $1675-$975=$700.
Then one same-day ticket is $700/20=$35.
One advance ticket is $65-$35=$30.
Make sense?