135 t the Sents are the 00 the Mai bal Comy seats sold by on

135, t the Sents are the (00. the Mai bal Comy seats sold by only hal a Saatsale sold, the atoss revenue is ere each kind ade orchestra seats main seats. balcon

Solution

Solution:

Let b = the number of balcony seats sold
Let m = the number of main seats sold
Then 600 - b - m = the number of orchestra seats sold
For the gross revenue we can write
25b + 35m + 50(600 - b - m) = 21000 ..... 1
If only half the orchestra seats are sold we can write
25b + 35m + 50(600 - b - m)/2 = 18000 ....2
Simplifying above two equation we get

25b + 15 m = 9000 ... A

10m = 3000 .... B

from A and B

We get

m = the number of main seats sold = 300

b= the number of balcony seats sold = 180

the number of orchestra seats sold = 600-300-180 = 120

Answer: 120 , 300 and 180