A brewing company suspects its beer will produce less weight gain, a possibly attractive marketing feature. Selecting from the population of his small town, two groups of beer drinkers agree to drink only one beer, either competitor’s or the Brewing Beer Company’s own beer, for one month, and agree to have their weight recorded at the end of the month. The data in weight change is below. Perform the appropriate statistical test.

Weight After Consuming Competitors’ Beer
Weight After Consuming Brewer’s Beer
4.2
3.9
6.3
10.4
-1.3
-2.5
3.3
6.5
7.9