Answer: 0.08 dollars per fluid ounce, or 8 cents per fluid ounce
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Step-by-step explanation:
1 quart = 32 fluid ounces
2 quarts = 64 fluid ounces (multiply both sides by 2)
He paid 5.12 dollars for 64 fluid ounces, so the unit rate is 5.12/64 = 0.08 dollars per fluid ounce, or 8 cents per fluid ounce.
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We can think of it this way in terms of an equation
5.12 dollars = 64 fluid ounces
5.12/64 dollars = 64/64 fluid ounces ... divide both sides by 64
0.08 dollars = 1 fluid ounce
We divided both sides by 64 to turn "64 fluid ounces" into "1 fluid ounce", due to how the term "unit rate" is set up. The term "unit" means "one". Basically we're finding the cost per 1 unit, or per 1 fluid ounce.