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How many cases of each brand should the breeder mix together to obtain a food that provides 3950 units of fiber, 3060 units of protein, and 2740 units of fat?
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Let x represent the number of cases of Brand A, y represent the number of cases of Brand B, z represent the number of cases of Brand C, and w represent be the number of cases of Brand D. There are four ways in which the breeder can mix brands to obtain a food that provides 3950 units of fiber, 3060 units of protein, and 2740 units of fat.
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BRAND Variable Fiber Protein Fat
A x 25 30 30
B y 100 80 70
C z 275 210 190
D w 100 80 60
Needed 3950 3060 2740
This is not a finished solution; but just a system of equations according to the described information and the given question.
This has one fewer equation than number of variables.