Answer:
n = 6 so 6 rooms
Explanation:
20n + 16.50 = 18n + 28.50
20n + 16.50 - 16.50 = 18n + 28.50 - 16.50
20n = 18n + 12
20n - 18n = 18n - 18n + 12
2n = 12
2n/2 = 12/2
n = 6
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