Answer:
Explanation:
a + c = 1000
9a + 5c = 6680
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9a + 9c = 9000
9a+ 5c = 6680
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4c = 2320
c = 580
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a+ 580 = 1000
a = 420
A = 420
C = 580
If you substitute the numbers into 9a + 5c = 6680, that should give you the right answer.