Question

how large a sample is needed in exercise 2 (above) if we wish to be 92% confident that our sample mean will be within 0.0005 inch of the true mean

Answer 1

To determine the sample size needed to be 92% confident that our sample mean will be within 0.0005 inch of the true mean, we can use the formula n = (z * s / E)^2.

Step-by-step explanation:

To determine the sample size needed to be 92% confident that our sample mean will be within 0.0005 inch of the true mean, we can use the formula:

n = (z * s / E)^2

Where n is the sample size, z is the z-score corresponding to the desired confidence level (in this case, 92%), s is the standard deviation of the population (which is unknown), and E is the maximum margin of error (0.0005 inch in this case).

Since we don't have the value of s, we need to calculate it by taking a sample and finding its standard deviation. Once we have the value of s, we can plug it into the formula to find the sample size.