# Question: Consider the profits as a percent of revenue for a

Consider the profits as a percent of revenue for a group of companies involved in petroleum and/or mining, as shown in Table 8.6.2.

a. Construct a sampling frame, viewing this list as a population of large petroleum and/or mining-related firms.

b. Draw a random sample of 10 firms, starting from row 13, column 2 of the table of random digits.

c. Compute the sample average.

d. Compute the standard error of the average, both with and without use of the finite-population correction factor.

e. Write a paragraph explaining and interpreting the standard error.

f. Compute the population mean.

g. Write a brief paragraph explaining the relationship among the sample average, population mean, and standard error.

a. Construct a sampling frame, viewing this list as a population of large petroleum and/or mining-related firms.

b. Draw a random sample of 10 firms, starting from row 13, column 2 of the table of random digits.

c. Compute the sample average.

d. Compute the standard error of the average, both with and without use of the finite-population correction factor.

e. Write a paragraph explaining and interpreting the standard error.

f. Compute the population mean.

g. Write a brief paragraph explaining the relationship among the sample average, population mean, and standard error.

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