Question

Suppose a chef claims that her meatball weight is less than 4 ounces, on average. Several of her customers do not believe her, so the chef decides to do a hypothesis test, at a 10% significance level, to persuade them. She cooks 14 meatballs. The mean weight of the sample meatballs is 3.7 ounces. The chef knows from experience that the standard deviation for her meatball weight is 0.5 ounces. H0: μ≥4; Ha: μ<4 α=0.1 (significance level) What is the test statistic (z-score) of this one-mean hypothesis test, rounded to two decimal places? Provide your answer below: $$

Test statistic=

Answer 1

Solution :

Given that,

Population mean = = 4

Sample mean = = 3.7

Population standard deviation = = 0.5

Sample size = n = 14

This is a left tailed test.

The test statistics,

Z =( - )/ (/n)

= ( 3.7 - 4 ) / ( 0.5 /14)

= -2.24

The test statistic = -2.24