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Hypothesis Testing, Confidence Interval

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NBC TV news, in a segment on the price of gasoline, reported last evening that the mean price nationwide is $1.50 per gallon for self-serve regular unleaded. A random sample of 35 stations in the Milwaukee, WI, area revealed that the mean price was $1.52 per gallon and that the standard deviation was $0.05 per gallon. At the .05 significance level, can we conclude that the price of gasoline is higher in the Milwaukee area? Calculate the p-value and interpret.


Babsie is a public affairs specialist at Park University. A press release issued by Babsie based on some research claims that Park University students study at least as much as the national average for students at four year universities. Across the nation, 73 percent of all students at four year universities study at least four hours per week. Seventy percent of one hundred randomly selected Park University students surveyed claimed to study more than four hours per week. Should the University retract its previous statement? Explain why or why not. Answer using a 95 percent confidence interval.


The weights (in pounds) of a sample of five boxes being sent by UPS are: 12, 6, 7, 3, and 10.
a. Compute the mean for this sample. Show your work!!
b. Compute the range for this sample. Show your work!!
c. Compute the variance for this sample. Show your work!!
d. Compute the standard deviation for this sample. Show your work!!

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Solution Summary

The solution provides step by step method for the calculation of testing of hypothesis, confidence interval and descriptive statistics. Formula for the calculation and Interpretations of the results are also included. Interactive excel sheet is included. The user can edit the inputs and obtain the complete results for a new set of data.

See Also This Related BrainMass Solution

One-Sample Hypothesis Test Confidence Intervals

One-Sample Hypothesis Test Confidence Intervals

Take a random sample and perform a t-test against a population mean (no time series for any parts of this project.) Test a hypothesis about a population mean. Besides the instructions above, explain what assumptions you made. Note: n must be between 15 to 20! Use no other sample sizes.

Use the same data as 1a and develop a 90% confidence interval and a 95% confidence interval for the population mean. Contrast this to 1a. What additional information or insight did this provide you over the traditional hypothesis testing.

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