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In: Statistics and Probability

1. Suppose that the distribution of scores on an exam is mound shaped and approximately symmetric....

1. Suppose that the distribution of scores on an exam is mound shaped and approximately symmetric. The exam scores have a mean of 110 and the 16th percentile is 85.

a. What is the 84th percentile?

b. What is the approximate value of the standard deviation of exam scores?

c. What is the z-score for an exam score of 90?

d. What percentile corresponds to an exam score of 160?

e. Do you think there were many scores below 35? Explain

Since a score of 35 is _______ one standard deviation two standard deviations  three standard deviations  below the mean, that corresponds to a percentile of

___ %. Therefore, there were ______ few many scores below 35.

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orchestra answered 2 years ago
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