The following data represent the age (in weeks) at which babies first crawl based on a survey of 12 mothers. The data are normally distributed and
Click the icon to view the table of critical values of the chi-square distribution.
Select the correct choice below and fill in the answer boxes to complete your choice. (Use ascending order. Round to three decimal places as needed.)
A. There is a
B. There is
C. If repeated samples are taken,
Step 1 :Given that the sample size (n) is 12 and the sample standard deviation (s) is 10.103 weeks. We are asked to construct a 95% confidence interval for the population standard deviation.
Step 2 :First, we calculate the degrees of freedom (df) which is given by n - 1. So, df = 12 - 1 = 11.
Step 3 :Next, we calculate the critical values of the chi-square distribution. The lower critical value (
Step 4 :Using a chi-square table or a statistical software, we find that
Step 5 :Then, we calculate the confidence interval for the population standard deviation. The lower bound is given by
Step 6 :Substituting the given values, we get the lower bound as
Step 7 :