=+If we view the 41 games with Gretzky as a random sample of all Oiler games in which Gretzky played and the 17 games without Gretzky as a random sample of all Oiler games in which Gretzky did not play, is there evidence that the mean number of goals scored by the Oilers is higher for games in which Gretzky played? Use a 5 .01.

Sample Sample n Mean sd Games with Gretzky 41 4.73 1.29 Games without Gretzky 17 3.88 1.18