# Class Width, Class Midpoints, and Class Boundaries

1. Identify the class width, class midpoints, and class boundaries for the given frequency distribution.

White Blood Cell Count for Males Frequency

4.0 - 5.9 8

6.0 - 7.9 15

8.0 - 9.9 11

10.0 - 11.9 5

12.0 - 13.9 1

2. The frequency distribution below shows arrival and delays for airplane flights

Arrival Delay min Frequency

(-60) - (-31) 14

(-30) - (-1) 26

0 - 29 9

30 - 59 2

60 - 89 2

Using the frequency distribution, construct a histogram.

Which part of the histogram depicts flights that arrived early?

Which part of the histogram depicts flights that arrived late?

3. Listed below are the top 10 annual salaries (in millions of dollars) of TV personalities

38.9, 36.3, 34.1, 27.8, 15.2, 12.8, 12.6, 9.4, 9.1,9.2

Calculate the mean, median, mode and mid-range.

Given that these are the top 10 salaries for TV personalities,

Do we know anything about the salaries in TV personalities in general?

4. Listed below are the top 10 annual salaries (in millions of dollars) of TV personalities

41, 39, 38, 30, 21, 19, 18, 17,16.6, 15.2

Calculate the range, variance, and Standard Deviation

Is the standard deviation of the sample a good estimate of the variation of salaries of TV personalities in general?

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1. Identify the class width, class midpoints, and class boundaries for the given frequency distribution.

White Blood Cell Count for Males Frequency

4.0 - 5.9 8

6.0 - 7.9 15

8.0 - 9.9 11

10.0 - 11.9 5

12.0 - 13.9 1

Interval Class Width Class Midpoints Class Boundaries

4.0-5.9 2 4.95 3.9-6.0

6.0-7.9 2 6.95 5.9-8.0

8.0-9.9 2 8.95 7.9-10.0

10.0-11.9 2 10.95 9.9-12.0

12.0-13.9 2 12.95 11.9-14.0

2. The frequency distribution below shows arrival and delays for airplane flights

Arrival Delay min Frequency

(-60) - (-31) 14

(-30) - (-1) 26

0 - 29 9

30 - 59 2

60 - 89 2

Using the ...

#### Solution Summary

The solution gives detailed steps on solving 4 descriptive statistics questions. The topic includes class width, class midpoints, class boundaries, mean, median, mode, mid-range, range, variance, Standard Deviation, histogram.