Transcript Lesson 6 - Coweta County Schools

• 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