# Sample Range, Variance, and SD for the Data Series

Sample Data Description.

United Package Service, Inc., delivers small parcels to business addresses in the Greater Detroit area. To learn more about the demand for its service, UPS has collected the following data on the number of deliveries per week for a sample of six customers:

3

4

5

6

2

4

A. Calculate the mean, median and mode measures of central tendency for the number of deliveries per week. Which measure does the best job of describing central tendency for this variable?

B. Calculate the range, variance and standard deviation for this data series. Which measure does the best job of describing the dispersion in this variable?

Sample Distribution.

Keiretsu Manufacturing, Ltd., has asked you to characterize the typical productivity of five manufacturing plants located in southeastern states. The following data show output per worker hour for each plant during the past month:

6

9

9

10

9

A. Calculate the sample mean, median and mode measures of central tendency for output per worker hour. Which measure does the best job of describing central tendency for this variable?

B. Calculate the sample range, variance and standard deviation for this data series. Which measure does the best job of describing the dispersion in this variable?

Confidence Intervals: t tests.

Materials Management, Ltd., is a small firm offering precious metal recycling services to industrial firms in the Sacramento, California area. The company takes in waste metal and chemical byproducts from industrial manufactures, removes any gold, and then disposes of remaining waste matter. To determine how much it should offer a new customer for their waste materials, Materials Management must accurately project the amount of gold to be obtained, on average, based on its study of the percentage of gold contained in a random sample of five batches of waste chemicals. The percentage of gold content obtained from each batch is:

1.00%

1.10%

1.05%

1.00%

1.10%

A. Calculate the mean, median and mode measures of central tendency for the percentage of gold content. Which measure does the best job of describing central tendency for this variable?

B. Calculate the sample range, variance and standard deviation for this data series, and the 99% confidence interval within which you would expect to find the population's true mean.

https://brainmass.com/statistics/quantative-analysis-of-data/sample-range-variance-sd-data-series-378047

#### Solution Preview

Mean: 3.66667 8.6 1.05%

Median: 3.5 9 1.05%

Mode: 2 9 ...

#### Solution Summary

The solution determines the sample range, variance, and standard deviation for the data series.