Explore Westonci.ca, the leading Q&A site where experts provide accurate and helpful answers to all your questions. Explore in-depth answers to your questions from a knowledgeable community of experts across different fields. Get quick and reliable solutions to your questions from a community of experienced experts on our platform.

An important factor in selling a residential property is the number of times real estate agents show a home. A sample of 23 homes recently sold in the Buffalo, New York, area revealed the mean number of times a home was shown was 24 and the standard deviation of the sample was 9 people.

Sagot :

Using the t-distribution, it is found that the 95% confidence interval for the mean number of people the houses were shown is (20.1, 27.9).

We have the standard deviation for the sample, hence the t-distribution is used to build the confidence interval. Important information are given by:

  • Sample mean of [tex]\overline{x} = 24[/tex].
  • Sample standard deviation of [tex]s = 9[/tex].
  • Sample size of [tex]n = 23[/tex]

The confidence interval is:

[tex]\overline{x} \pm t\frac{s}{\sqrt{n}}[/tex]

In which t is the critical value for a 95% confidence interval with 23 - 1 = 22 df, thus, looking at a calculator or at the t-table, it is found that t = 2.0739.

Then:

[tex]\overline{x} - t\frac{s}{\sqrt{n}} = 24 - 2.0739\frac{9}{\sqrt{23}} = 20.1[/tex]

[tex]\overline{x} + t\frac{s}{\sqrt{n}} = 24 + 2.0739\frac{9}{\sqrt{23}} = 27.9[/tex]

The 95% confidence interval for the mean number of people the houses were shown is (20.1, 27.9).

A similar problem is given at https://brainly.com/question/15180581