Answer:
35b+75f = 27750
25b+60f = 21750
Explanation:
Letting b represent the number of balcony seats, we know that each balcony seat at the concert costs $35; this gives us 35b.
Letting f represent the number of floor seats, we know that each floor seat at the concert costs $75; this gives us 75f.
Together this gives us 35b+75f.
We know that the total revenue for the sold out concert is $27750; this gives us
35b+75f = 27750.
Each balcony seat at the theatrical production costs $25; this gives us 25b.
Each floor seat at the theatrical production costs $60; this gives us 60f.
Together this gives us 25b+60f.
We know that the total revenue for the sold out theatrical production is $21750; this gives us
25b+60f = 27750.