Answer:
Apples and Peaches
Explanation:
It is convenient to compare the prices for 3 lbs of each of the fruits.
Multiply the price and quantity of Apples by 4:
... 4×(3/4 lb) = 4×$1.59
... 3 lb = $6.36 . . . . for apples
Multiply the price and quantity of Plums by 6:
... 6×(0.5 lb) = 6×$1.15
... 3 lb = $6.90 . . . . for plums
The two lowest-priced fruits are apples (6.36/(3 lb)) and peaches (5.37/(3 lb)).
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Comment on the best deal
No criteria are provided for determining the best deal. Though plums are higher-priced, they have somewhat higher polyphenol content than apples or peaches, so may provide the best deal in terms of nutrition per dollar.