For a recent year, the mean fare to fly from Charlotte, North Carolina, to Seattle, Washington, on a discount ticket was $ 267. A random sample of round-trip discount fares on this route last month givs:
$321 $286 $290 $330 $310 $250 $270 $280 $299
$265 $291 $275 $281
At the .01 significabce level, cn we conclude that the mean fare has increased ? What is the p-value ?