Question

A chocolate chip cookie manufacturing company recorded the number of chocolate chips in a sample of 50 cookies. The mean is 22 04 and the standard deviation is 288 Construct a 80% confidence interval estimate of the standard deviation of the numbers of chocolate chips in all such cookies Click the icon to view the table of Chi-Square critical values □ chocolate chips-os □ chocolate chips (Round to two decimal places as needed.) Enter your answer in the edit fields and then click Check Answer. Clear All All parts showing 7-56 PM ort w 8 6

Answer 1

EXCEL (PH Stat) output:

Confidence Interval Estimate for the Population Variance Data Sample Size Sample Standard Deviation Confidence Level 50 2.88 80% Intermediate Calculations Degrees of Freedom Sum o Single Tail Area Lower Chi-Square Value Upper Chi-Square Value 49 406.4256 0.1 36.8182 62.0375 uares Results Interval Lower Limit for Variance Interval Upper Limit for Variance 6.5513 11.0387 Interval Lower Limit for Standard Deviation Interval U 2.5595 r Limit for Standard Deviation 3.3225 The 80% confidence interval estimate ofthe standard deviation is 256 chocolate chips < σ < 332 < chocolate chips