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g Keith sampled 10 private universities in Colorado and recorded the tuition cost. Keith wants to test the hypothesis that the tuition of these 10 universities is more expensive than the national average tuition, which is $29,056 with a population standard deviation of $3,339. z equals fraction numerator x with bar on top minus mu over denominator begin display style fraction numerator sigma over denominator square root of n end fraction end style end fraction If the sample mean is $31,650, what is the z-score

User Mfurseman
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2 Answers

3 votes

Answer:

69

Explanation:

User Kimmi
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4 votes

Answer:

Z score=2.46.

Explanation:

The Z score for sample mean $31,650 can be computed by using following formula


Z=(xbar-Population mean)/((sigma)/(√(n) ) )

Here, sample mean=xbar=31650

population standard deviation=sigma=3339

population mean=29056

and sample size=n=10.


Z=(31650-29056)/((3339)/(√(10) ) )


Z=(2594)/(1055.885)

Z=2.4567

Z=2.46 (rounded to two decimal places).

Hence the resultant z-score is 2.46.

User Yorjo
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