Answer: (24.02,25.98)
Step-by-step explanation:
Answer:
Step-by-step explanation:
Given : Sample size : n= 100
Sample mean : [tex]\overline{x}=25\text{ hours}[/tex]
Standard deviation : [tex]\sigma=5\text{ hours}[/tex]
Significance level : [tex]\alpha: 1-0.95=0.05[/tex]
Critical value : [tex]z_{\alpha/2}=1.96[/tex]
The confidence interval for population mean is given by :-
[tex]\overline{x}\pm\ z_{\alpha/2}\dfrac{\sigma}{\sqrt{n}}\\\\=25\pm(1.96)\dfrac{5}{\sqrt{100}}\\\\=25\pm0.98\\\\=(25-0.98,\ 25+0.98)=(24.02,25.98)[/tex]
Hence, the 95% confidence interval for the population mean of training times is (24.02, 25.98).