Answers are: choice C, choice D
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Explanation:
Let
a = adult admission fee
c = child admission fee
Focus on row 1 for now
45a = cost of having 45 adults total
30c = cost of having 30 children total
45a+30c = total cost of 45 adults and 30 children = 315
So, 45a+30c = 315 is the first equation
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Now move to row 2
For similar reasoning, 50a+40c = 370 is the other equation
50a = cost of having 50 adults buy a ticket
40c = cost of having 40 children buy a ticket
50a+40c = total cost of having 50 adults and 40 children = 370
