They've always said the lottery is aimed at people who are bad at math. However, lottery tickets at least sell you a daydream against astronomical odds. Sometimes, you get sold a bill of goods, by people figuring you're one of those kids who didn't get through math in school. Or maybe THEY were the ones who flunked?
Seen on ebay: "BPAL perfume Carnival Diabolique, 9 5ml bottles $202 or best offer." Let's see, the line in question sells for $20 a bottle... Gee, if I'm really math challenged, should I offer $220?
Or how about this gem from subscription renewal: "Renewal savings! Two years for the price of one, or three years for the price of two!"