The admission fee for an amusement park is $15 for adults and $7.50 for children. One weekend, 4502 people paid admission for the amusement park, and the park made $52,515. How many adults and how many children paid to go to the amusement park that weekend?
A. a • c = 4502
15a • 7.5c = 52,515
B. a + c = 22.5
15a + 7.5c = 57,017
C. a + c = 4502
15a + 7.5c = 52,515
D. a + c = 52,515
15a + 7.5c = 4502