Question 42385
This is a proportion problem. 
Compare Dollars to Dollars and Patties to patties.
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$5.80/12 patties = $7.00/x patties
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Cross-multiply and solve for x:
5.80x = (12)(7)
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5.80x = 84
x = 14.48 or 14 patties.

Another method is to find out how much a single pattie would cost:
If 12 patties cost $5.80, than divide $5.80/12 = $0.483 per pattie.
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If you have $7.00 to spend and each pattie is $0.483 per pattie, than:
7/0.483 = 14.48 or 14 whole patties.