Question

A quality control specialist for a restaurant chain takes a random sample of size 14 to check the amount of soda served in the 16 oz. serving size. The sample mean is 13.30 with a sample standard deviation of 1.58. Assume the underlying population is normally distributed.

Find the 95% confidence interval for the true population mean for the amount of soda served. (Round your answers to two decimal places.)

(____, ____)

Answer 1

we have mean() = 13.30, sample standard deviation (s) = 1.58, sample size(n) = 14

and from student's t distribution table, we can find out the t critical value for degree of freedom =n-1 = 14-1 = 13, we get 2.16

using the formula for confidence interval, we get

Confidence interval =

setting the given values, we get

Confidence interval = = (12.39, 14.21)

So, the required 95% confidence interval for the true population mean fo the amount of sode served is  (12.39, 14.21)