Mrs. Heileman occasionally drinks beer. (Guess which brand.) She consumes one case in 20 weeks. She can buy beer in disposable cans for $25.20 per case or for

$24.00 per case of returnable bottles if she pays a $3.00 refundable deposit at the time of purchase. If her discount rate is Vi percent per week, how much in present value dollars does she save by buying the returnable bottles and thereby losing the use of the $3.00 deposit for 20 weeks?

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