posted by Jennifer .
For $1.80 a grocer buys a case of fruit which contains 12 dozen. She knows that tow dozen will spoil before she sells them. At what price per dozen must she sell the good ones to gain 1/3 of the whole cost?
(1/3) * $1.80 = $0.60. = Income.
P = $0.60 / (12-2) = $0.06 / doz.