Question

Construct the confidence interval for the population mean μ.

c= 0.98, x̄=6.6, σ=0.7, n=41

A 98 % confidence interval for μ is ( _ , _ )

Round two decimal places as needed.

Answer 1

Solution :

Given that,

Point estimate = sample mean = = 6.6

Population standard deviation =    = 0.7

Sample size = n = 41

At 98% confidence level

= 1 - 98%  

= 1 - 0.98 =0.02

/2 = 0.01

Z/2 = Z0.01 = 2.326

Margin of error = E = Z/2 * ( /n)

= 2.326 * ( 0.7 /  41 )

= 0.25

At 98% confidence interval estimate of the population mean is,

  ± E

6.6 ± 0.25   

( 6.35, 6.85 )