The impurity level (in ppm) is routinely measured in a chemical product. The following data were...

The impurity level (in ppm) is routinely measured in a chemical product. The following data were observed in a recent test:

2.4 2.6 1.9 1.6 1.9 2.6

1.9 2.4 2.0 2.5 2.6 2.3

2.0 1.9 1.5 1.7 2.0 1.9

2.3 1.9 2.4 1.8 2.6 2.6

You need to test if the true mean impurity level is lesser than 2.5 ppm.

What is the type of statistical test procedure that should be used to test the hypotheses? Explain.

Construct a 95% confidence interval. Test the hypotheses using the confidence interval. Interpret the test result clearly.

Test the hypotheses using the Test Statistic / Critical Value method (you must clearly indicate the test statistic, and the critical value(s) used). Do you get the same answer as part (c)? If your answer is the same as (c), you do not have to interpret again. Otherwise, interpret the test findings.

What is the P value of the test? Test the hypotheses using the P value. Do you get the same answer as parts (c) and (d)? If your answer is the same as (c) and (d), you do not have to interpret again. Otherwise, interpret the test findings.

Expert Solution

orchestra answered 1 year ago

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