Question

Construct the confidence interval for the population variance for the given values. Round your answers to one decimal place.

n=13, s2=8.6, and c=0.98

Answer 1

Solution :

Given that,

Point estimate = s2 = 8.6

2R = 2/2,df = 26.217

2L = 21 - /2,df = 3.570

The 98% confidence interval for 2 is,

(n - 1)s2 / 2/2 < 2 < (n - 1)s2 / 21 - /2

(12)(8.6) / 26.217 < 2 < (12)(8.6) / 3.570

3.9  < 2 < 28.9  

(3.9 , 28.9)