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The standard deviation of the daily temperatures in Los Angeles in 2014 was 4.2 degrees Fahrenheit....

The standard deviation of the daily temperatures in Los Angeles in 2014 was 4.2 degrees Fahrenheit. A random sample of 28 days in 2018 resulted in a standard deviation of 6.0 degrees Fahrenheit. Has there been a significant change in the variance of the temperatures (α=0.05?)

a) Formulate the hypotheses.

b) Calculate the test statistics (chi-square value) and test the hypotheses. What is the conclusion?

c) A 95% confidence, what is the interval estimate of the variance for the population

Math   Statistics-And-Probability   
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