Suppose a chef claims that her meatball weight is less than3

ounces, on average. Several of her customers do not believe her, so the chef decides to do a hypothesis test, at a1%

significance level, to persuade them. She cooks25

meatballs. The mean weight of the sample meatballs is2

ounces. The chef knows from experience that the standard deviation for her meatball weight is0.5

ounces.

• H
• 0
• :3
• ;H
• a
• :<3
• =0.01
• (significance level)

What is the test statistic (z

-score) of this one-mean hypothesis test, rounded to two decimal places?