Answer: 12a+7.50c ≥ 325 and a+c ≤ 36
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Work Shown:
a = number of adults
c = number of children
12a = revenue from just the adults
7.50c = revenue from just the children
12a+7.50c = total revenue
total revenue ≥ $325
12a+7.50c ≥ 325 is part of the answer
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a+c = total number of people
total number of people ≤ 36
a+c ≤ 36 is the other part of the answer