Answer:
• 800 pavilion seats
• 800 lawn seats
Explanation:
Let p represent the number of pavilion seats sold. Then 1600-p is the number of lawn seats sold. Total revenue is ...
25p +20(1600 -p) = 36000
5p + 32000 = 36000
5p = 4000
p = 800 . . . . . . . . . . number of pavilion seats sold
1600-p = 800 . . . . . number of lawn seats sold
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You can work these problems in your head. Consider that all seats were sold at the lower price. Then revenue would be 1600·20 = 32000. It was 36000 -32000 = 4000 more than that. The difference in ticket price is 25 -20 = 5 dollars, so there must have been 4000/5 = 800 higher-priced tickets sold. (Compare this working to the math above. You will find it substantially similar.)