Answer:
z = 10
Step-by-step explanation:
The value of the z-statistic is given by:
In which:
X is the measured value.
is the expected value.
is the standard deviation of the sample.
is the standard deviation of the population.
In this question:
The mean length was 2.9 inches, and the population standard deviation is 0.1 inch.
This means that
Random sample of 100 screws.
This means that n = 100.
To see if the batch of screws has a significantly different mean length from 3 inches, what would the value of the z-test statistic be?
3 inches, so