# Hypothesis Testing & Confidence Interval

Temperature measurements are recorded at 40 randomly selected different locations for a particular city. A sample mean of 20 degrees Celsius is obtained with a standard deviation of 1.5 degrees.. There are no outliers in the sample measurements. Test the claim that the population mean is 21 degrees Celsius. Use a 0.05 significance level.

a) (3) Ho: H1:

b) (2) State the requirements for this test. ______________________________________________

______________________________________________________________________________________________

c) (2) What are the critical values of the test statistic? _______________________

d) (2) What is the calculated value of the test statistic? ________________________

e) (2) What is the p-value of the test statistic? ________________________

f) (3) Label the diagram to the right and shade the rejection region(s).

g) (4) State and support your decision about the null hypothesis.

h) (2) Construct a 95% confidence interval for the mean temperature in the city.

i) (3) Based on the hypothesis test and confidence interval what can you conclude about the average temperature in this city?

https://brainmass.com/statistics/confidence-interval/testing-hypothesis-confidence-interval-population-mean-390199

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Statistics

Temperature measurements are recorded at 40 randomly selected different locations for a particular city. A sample mean of 20 degrees Celsius is obtained with a standard deviation of 1.5 degrees.. There are no outliers in the sample measurements. Test the claim that the population mean is 21 degrees Celsius. Use a 0.05 significance level.

Answers

a) (3)

Ho: The average temperature in the city = 21 degrees Celsius (µ = 21)

H1: The average temperature in the city ≠ 21 degrees Celsius (µ ≠ 21)

b) (2) State the requirements for this test.

Sample is randomly selected from the population.

Sample must be large (n ≥ 30)

c) (2) What are the critical values of the test statistic?

Critical values are obtained ...

#### Solution Summary

The solution provides step-by-step method for the calculation of testing of hypothesis and confidence interval of population mean. 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.