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If a set of test scores has a standard deviation of zero, what does this mean about the scores?

A set of data items is normally distributed with a mean of 60 and a standard deviation of 8 . In Exercises 33-48, convert each data item to a z-score. 52

Find two \(z\)-scores so that \(40 \%\) of the data in the distribution lies between them. (More than one answer is possible.)

A set of data items is normally distributed with a mean of 60 and a standard deviation of 8 . In Exercises 33-48, convert each data item to a z-score. 44

Two classes took a statistics test. Both classes had a mean score of 73 . The scores of class \(A\) had a standard deviation of 5 and those of class B had a standard deviation of 10 . Discuss the difference between the two classes' performance on the test.

A woman insists that she will never marry a man as short or shorter than she, knowing that only one man in 400 falls into this category. Assuming a mean height of 69 inches for men with a standard deviation of \(2.5\) inches (and a normal distribution), approximately how tall is the woman?

The placement test for a college has scores that are normally distributed with a mean of 500 and a standard deviation of 100 . If the college accepts only the top \(10 \%\) of examinees, what is the cutoff score on the test for admission?

A set of data items is normally distributed with a mean of 60 and a standard deviation of 8 . In Exercises 33-48, convert each data item to a z-score. 48

Describe how to construct a frequency polygon from a histogram.

Make Sense? In Exercises 47-50, determine whether each statement makes sense or does not make sense, and explain your reasoning. The mean can be misleading if you don't know the spread of data items.