If things are going right, the quart bottles of George Adams Ale come off the assembly line with a mean of 32.2 ounces and a standard deviation of .3 ounces.  But, if things aren't working, the means could be almost anything.

We just took a sample of 25 bottles and the mean turned out to be 32.4.  Could this mean be from that distribution of means which happen if things are going right?  Or is it more likely to be from some other distribution of means?  Let's be 95% confident.