Researchers wanted to determine if carpeted rooms contained more bacteria than uncarpeted rooms. To determine the amount of bacteria in a room, researchers pumped the air from the room over a Petri dish at the rate of 1 cubic foot per minute for eight carpeted rooms and eight uncarpeted rooms. Colonies of bacteria were allowed to form in the 16 Petri dishes. The results are presented in the table. A normal probability plot and boxplot indicate that the data are approximately normally distributed with no outliers. Do carpeted rooms have more bacteria than uncarpeted rooms at the α = 0.05 level of significance?

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Carpeted Rooms (bacteria/cubic foot) Uncarpeted Rooms (bacteria/cubic foot) 11.8 8.2 7.1 13.0 10.8 10.1 14.6 14.0 12.1 8.3 3.8 7.2 12.0 11.1 10.1 13.7