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According to the American Academy of Ophthalmology, 25% of Americans have brown irises. A random survey of students at a local community college found that 58 out of 175 had brown irises. What is the test statistic (ie the Z score) for this sample of students

User Opmet
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1 Answer

7 votes

Answer:

2.49

Explanation:

Given X= 58

N = 175.

P = 25% = 0.25.


P' = (X)/(N) = (58)/(175) = 0.3314\\Z = \frac{P'-P}{\sqrt{(pq)/(N) } }

Now plugging the values we get


= \frac{0.3314-0.25}{\sqrt{(0.25*0.75)/(175) } }

=2.49

User Loriensleafs
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