The best deal is to buy 12 pounds. Winnie should buy the 12 pound bags.
Given that, there are 4 deals, i.e.
To get the best deal, calculating the cost of one pound for each deal.
For deal 1, Cost of one pound is [tex]\dfrac{\$4.99}{4.2} = \$1.19[/tex]
For deal 2, Cost of one pound is [tex]\dfrac{\$9.27}{8.5} = \$1.09[/tex]
For deal 3, Cost of one pound is [tex]\dfrac{\$11.04}{12} = \$0.92[/tex]
For deal 4, Cost of one pound is [tex]\dfrac{\$18.99}{20} = \$0.95[/tex]
Here the lowest cost of one pound is $0.92 which is deal 3.
So, the best deal is to buy 12 pounds. Winnie should buy the 12 pound bags.
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