A special coating is applied to several scale model engine n

A special coating is applied to several scale model engine nacelle body shapes to determine if it reduces the drag coefficient. The following data are the drag coefficient before the coating is applied and after.

Perform a hypothesis test to determine if there is evidence at the 0.05 level of significance to support the claim that the coating reduces the drag coefficient.

What is the test value for this hypothesis test?

Answer: Round your answer to two decimal places.

What is the P-value for this hypothesis test?

Answer: Round your answer to three decimal places.

What is your conclusion for this test? Choose one.

1. There is sufficient evidence to show the coating reduces the drag coefficient.
2. There is not sufficient evidence to show that the coating reduces the drag coefficient.
3. There is sufficient evidence to show that the drag coefficient changed after the coating was applied.
4. There is sufficient evidence to show that the drag coefficient increased after the coating was applied.

Answer: Enter only a 1, 2, 3 or 4 for your answer.

Solution

What is the test value for this hypothesis test?

t= mean difference/(s/vn)

=0.032167/(0.050408/sqrt(6))

=1.56

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What is the P-value for this hypothesis test?

It is a one-tailed test.

The degree of freedom =n-1=6-1=5

The p-value= P(t with df=5>1.56) =0.0898 (from student t table)

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What is your conclusion for this test?

2. There is not sufficient evidence to show that the coating reduces the drag coefficient.