Answer:
Let a be the cost of an adult ticket and c be the cost of a child's ticket.
40a + 25c = 56,050--->40a + 25c = 56,050
a + c = 1600-------------->40a + 40c = 64,000
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15c = 7,950
c = 530, a = 1,070
530 child tickets, 1,070 adult tickets