Answer:
z = -2.24
Step-by-step explanation:
The test statistic for testing a claim about a mean (when we know the standard deviation of the population) is:
[tex]z=\frac{x-u}{\frac{s}{\sqrt{n} } }[/tex]
where z is the test statistic, x is the sample mean, u is the population mean, s is the standard deviation of the population and n is the number of meatballs in this case.
[tex]z=\frac{3.7-4}{\frac{0.5}{\sqrt{14} } }=-2.24[/tex]