Using confidence interval concepts, it is found that:
a) The point estimate is the sample mean.
b) The confidence interval is:
c) If $1411 is between the bounds of the interval yes, otherwise no.
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- At item a, it asks to provide a point estimate for the population mean, which is the sample mean
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Item b:
- In the spreadsheet, it is possible to find the <em>standard deviation for the sample</em>, thus, the t-distribution is used.
- The confidence interval will be given by:
In which:
is the sample mean.
- T is the critical value, from the t-distribution, with a two-tailed area of
and n-1 degrees of freedom.
- s is the standard deviation for the sample.
- n is the sample size.
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Item c:
We have to check if 1411 is between and
.
- If it is, the interval includes the National Average, otherwise, it does not.
A similar problem is given at brainly.com/question/24232455