Question

Use technology to construct the confidence intervals for the population variance σ2 and the population standard deviation σ2

Assume the sample is taken from a normally distributed population.

c=0.980.98​,

s2=4.844.84​,

n=2727

The confidence interval for the population variance is

(Round to two decimal places as​ needed.)

Answer 1

(a)

Use technology to construct the confidence intervals for the population variance σ² :

n = 27

s² = 4.84

= 0.02

df = 27 - 1 = 26

Confidence Interval:

Low end:

By Technology: Using the function CHIINV (0.01,26) on Excel, we get:

Low End:

High End:

By Technology: Using the function CHIINV (0.99,26) on Excel, we get:

High End:

Confidence Interval:

2.76 < < 10.32

(b)

Use technology to construct the confidence intervals for the population standard deviation σ

n = 27

s² = 4.84

= 0.02

df = 27 - 1 = 26

Confidence Interval:

Low end:

By Technology: Using the function CHIINV (0.01,26) on Excel, we get:

Low End:

High End:

By Technology: Using the function CHIINV (0.99,26) on Excel, we get:

High End:

Confidence Interval:

1.66 < < 3.21