Question

30. Use technology to construct the confidence intervals for the population variance sigmasquared and the population standard deviation sigma. Assume the sample is taken from a normally distributed population. cequals0.90​, sequals34​, nequals17 The confidence interval for the population variance is ​( nothing​, nothing​). ​(Round to two decimal places as​ needed.)

Answer 1

30)

Solution :

Given that,

s = 34

Point estimate = s² = 1156

n = 17

Degrees of freedom = df = n - 1 = 16

²_L = ²_/2,df = 26.296

²_R = ²_{1 - /2,df} = 7.962

The 90% confidence interval for ² is,

(n - 1)s² / ²_/2 < ² < (n - 1)s² / ²_{1 - /2}

16 * 1156 / 26.296 < ² < 16 * 1156 / 7.962

707.37 < ² < 2323.15

( 707.37 , 2323.15)