In: Statistics and Probability
High school graduates: The National Center for Educational Statistics reported that 82% of freshmen entering public high schools in the U.S. in 2009 graduated with their class in 2013. A random sample of 135 freshmen is chosen.
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a. |
Page 333 Find the mean μ. |
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b. |
Find the standard deviation σ. |
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c. |
Find the probability that less than 80% of freshmen in the sample graduated. |
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d. |
Find the probability that the sample proportion of students who graduated is between 0.75 and 0.85. |
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e. |
Find the probability that more than 75% of freshmen in the sample graduated. |
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f. |
Would it be unusual if the sample proportion of students who graduated were more than 0.90? |