According to an article in the New York Times, a new trend has been introduced by some of America's finest restaurants: refusing to offer diners bottled water, and pushing instead the restaurant's filtered tap water. A restaurant owner is considering following this new trend but wants to research the option. The owner collects a random sample of paired observations on the numbers of bottled water orders per night and the number of customers who agreed to drink filtered tap water that night.

The data are (15, 8), (17, 12), (25, 10), (19, 3), (28, 5), (17, 18), (12, 13), (20, 11), (16, 18).

Is there evidence that tap water can be as popular as bottled water?