A store normally sells each of its DVDs for \$20. At a sale, Phyllis buys two DVDs at the regular price and gets a third DVD for half price. This is the same rate of discount as getting
(A) 2 for the price of 1 (B) 3 for the price of 2 (C) 4 for the price of 3 (D) 5 for the price of 4 (E) 6 for the price of 5
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Source: CEMC, University of Waterloo,
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Statement reproduced verbatim; metadata (topic, difficulty) added by this project. Solutions are the publisher's, linked not copied.