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• How do I collect sample data from population? 7.6 Sample Data and Populations Example 1 Collect data by randomly sampling A gym has 467 female members and 732 male members. The marketing director of the gym wants to form a random sample of 30 female members and a separate random sample of 60 male members to answer some survey questions. Each female member has a membership number from 1 to 467 and each male member has a membership number from 1001 to 1732. Use a graphing calculator to select the members who will participate in each random sample. Random sample of female members: Using the random integer feature of a graphing calculator to generate ____ 30 random integers between __ 1 and ____ 467 produces the following sample answer. The random sample of female members have membership numbers: ___________________________ Answers will vary 7.6 Sample Data and Populations Example 1 Collect data by randomly sampling A gym has 467 female members and 732 male members. The marketing director of the gym wants to form a random sample of 30 female members and a separate random sample of 60 male members to answer some survey questions. Each female member has a membership number from 1 to 467 and each male member has a membership number from 1001 to 1732. Use a graphing calculator to select the members who will participate in each random sample. Random sample of male members: Using the random integer feature of a graphing calculator to generate ____ 60 random integers between _____ and 1732 _____ produces the following sample answer. 1001 The random sample of male members have membership numbers: ___________________________ Answers will vary 7.6 Sample Data and Populations Checkpoint. Complete the following exercises. 1. In Example 1, suppose there are 245 female members and 532 male members. The marketing director wants to form a random sample of 12 female members and a separate random sample of 15 male members. Use a graphing calculator to select the members who will participate in each random sample. Generate 12 random integers between 1 and 245. Generate 15 random integers between 1001 and 1532. 7.6 Sample Data and Populations Example 2 Compare statistics and parameters A company wants to know how many minutes it takes their employees to drive to work each day. Gillian and Ted, two employees, collect separate random samples. Their results are displayed below. The population mean is 18.4 and the population standard deviation is about 15.6. Compare the means and standard deviations of the random samples to the population parameters. Gillian 10, 8, 20, 42, 5, 32, 8, 9, 17, 27 Ted 23, 18, 6, 47, 23, 31, 10, 13, 7, 3, 14, 55, 25, 19, 23 Gillian : Ted : x 17.8 11.7 x 21.1 14.0 7.6 Sample Data and Populations Example 2 Compare statistics and parameters A company wants to know how many minutes it takes their employees to drive to work each day. Gillian and Ted, two employees, collect separate random samples. Their results are displayed below. The population mean is 18.4 and the population standard deviation is about 15.6. Compare the means and standard deviations of the random samples to the population parameters. Gillian 10, 8, 20, 42, 5, 32, 8, 9, 17, 27 Ted 23, 18, 6, 47, 23, 31, 10, 13, 7, 3, 14, 55, 25, 19, 23 The mean of Gillian’s sample is ___________ less than the population mean, while the mean of Ted’s sample is _______________ greater th an the population mean. The standard deviation of both samples are ___________ less than the population standard deviation. 7.6 Sample Data and Populations Checkpoint. Complete the following exercises. 2. In Example 2, suppose the population mean is 14.5 and the population standard deviation is 10.4. Compare the means and standard deviations of the random samples to the population parameters. The means and standard deviations of both samples are greater than the population mean and population standard deviation. 7.6 Sample Data and Populations Pg. 286, 7.6 #1-10