Brand A: 32 oz. for $2.90
Brand B: 20 oz. for $2.09
Brand C: 48 oz. for $4.00
Brand D: 10 oz. for $1.25
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To solve you will have to divide cost/oz.
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Brand A: 1 oz. for $0.09
Brand B: 1 oz. for $0.10
Brand C: 1 oz. for $0.08
Brand D: 1 oz. for $0.13
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So, Brand C is the best buy because it is the cheapest.
BOLDED THINGS ARE IMPORTANT LOL