The local CD shop operates an unusual discount policy. The discount on the next purchase is worked out on the current purchase in the following way: for every whole dollar spent you get 0.5% discount on the next purchase. For example, if you purchased $8.99 on the first purchase, you would then get a 4% discount on the next purchase and so on. You can make as many purchases as necessary.
You need to buy 7 CDs, costing, $11.50, $12.00, $12.00, $12.50, $13.00, $13.00 and $14.50 – what is the cheapest method of buying them?
Hint
Make 2 purchases.
Answer
Purchase 1: $11.50, $12.00, $12.00, $12.50 = $48.00 (which gives a 24% discount on the next purchase).
Purchase 2: $13.00, $13.00, $14.50 = $40.50 minus 24% discount = $30.78. For a total cost of $78.78 dollars.
