Question
A random sample of 32 textbook prices is taken from a local college bookstore . The mean of the sample is bar (x)=74.22 , and the sample standard deviation is s=23.44 Use a 95% confidence level and find the margin of error for the mean price of all textbooks in the bookstore.
Answer
4.2
(348 Votes)
Timothy
Elite · Tutor for 8 years
Answer
10.23
Explanation
The margin of error for a confidence interval can be calculated using the formula:E = Z * (s/���n)where:E is the margin of error,Z is the Z-score (which depends on the desired level of confidence),s is the standard deviation of the sample, andn is the size of the sample.For a 95% confidence level, the Z-score is approximately 1.96.Substituting the given values into the formula, we get:E = 1.96 * (23.44/���32) = 10.23So, the margin of error for the mean price of all textbooks in the bookstore is approximately $10.23.