Luisa wants to purchase 2 DVDs. At Stay and Play DVDs are on sale-buy 1 get 1 free. At Barney's the DVDs are 25% off. Which is a better deal?
Assume the DVD costs \(d\), For the first option, you would only pay the cost of one \(d\). For the second option, you would pay the cost of \(d + 0.75d\), because the first one costs \(d\), and the second one costs \(0.75d\). Thus, the first option is the better deal.