SOLUTION: A gas station manager thinks the average motorist changes their oil less than the recommended two times per year. In a survey 15 car owners were asked how many times they changed

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Question 285878: A gas station manager thinks the average motorist changes their oil less than the recommended two times per year. In a survey 15 car owners were asked how many times they changed their oil in the past year. Here are the results:
1 1 2 1 2
2 0 1 0 1
2 3 1 3 0
The value of the test statistic is equal to _____________ ?
Answer between two and four decimals
Thank you for any help that you can provide!
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
A gas station manager thinks the average motorist changes their oil less than the recommended two times per year. In a survey 15 car owners were asked how many times they changed their oil in the past year. Here are the results:
1 1 2 1 2
2 0 1 0 1
2 3 1 3 0
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sample mean = (sum of the data)/15 = 20/15 = 4/3
sample standard deviation: 0.976
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test statistic = t(4/3) = (4/3 - 2)/[0.976/sqrt(15)] = -0.0882

The value of the test statistic is equal to -0.0882
Answer between two and four decimals
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Cheers,
Stan H.