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3 years ago

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The library sells 376 books at its annual used-book fundraiser. They take in a total of $2120. Childrens books cost $4, and adul

ts books cost $7. How many childrens books did they sell?
Let c = number of childrens books sold, and let a = the number of adult books sold.

which system of equations can the librarians use to solve this problem?

A. 4c+7a = 376
c+a = 2120
a= 376-c
B. 7c+4a = 2120
a+c = 376
C. 4a+7c=2120
c+a = 376
D. 4c + 7a = 2120

1 answer:

igomit [66]3 years ago

7 0

$Answer: \left\{\begin{array}{ccc}4a+7c=2120\\a+c=376\end{array}\right$

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