Answer:
The right solution is "3.29, 3.57".
Step-by-step explanation:
Seems that the given problem is incomplete. Below is the attachment of the complete and appropriate query.
The given values are:
Randomly selected adults,
[tex]n = 105[/tex]
Mean,
[tex]\bar{x} = 3.42[/tex]
Standard deviation,
[tex]s = 0.75[/tex]
Now,
At 95% confidence level if given by,
= [tex]\bar{x} \ \pm \ Z_{\frac{\alpha}{2} }\times \frac{s}{\sqrt{n} }[/tex]
On putting the given values, we get
= [tex]3.42 \ \pm \ Z_{\frac{0.05}{2} }\times \frac{0.75}{\sqrt{105} }[/tex]
= [tex]3.42 \ \pm \ 1.96\times 0.073[/tex]
= [tex]3.42 \ \pm \ 0.143[/tex]
= [tex]3.29, 3.57[/tex]
