39　Complex Math Problem 复杂的数学题

I couldn't decide whether to go to Salt Lake City or Denver for vacation, so I called the airlines to get prices. “Airfare to Denver is $300,” the salesperson replied. “And what about Salt Lake City?” “We have a really great rate to Salt Lake—$99,” she said. “But there is a stopover.” “Where?” “In Denver,” she said.

我不能决定到底是到盐湖城还是到丹佛市去度假，所以打电话到航空公司去问问票价。售票员说：“到丹佛市去的机票价300美元。”“那到盐湖城去的呢？”她说：“我们有优惠价99美元到盐湖城。不过途中要停一下。”“在哪里停？”“在丹佛市。”