Avon High School Name
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ACE College Algebra II
Worksheet 12-2 Sampling, Surveys, and Standard Deviation Period
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Identify the sampling method. Then identify any bias in each method.
1. A teacher committee wants to find how much time students spend reading each week. They ask students as they enter the library.
2. The students planning the junior class party want to know what kinds of pizza to buy. They ask the pizza restaurant what kinds sell the most.
3. The county road department wants to know which roads cause the most concern among the residents of the county. They ask the local restaurants to hand out survey forms for customers to return by mail.
Identify any bias in each survey question.
4. Do you believe that kids should go to school year-round because they are responsible for the rise in petty crime during the summer months?
5.
Isn’t our local government not aware of our current traffic problems?
6.
Shouldn’t our school do its part to end global warming by starting a recycling program?
7. a. What sampling method could you use to find the percent of people in your community who support tougher penalties for running red lights? b. What is an example of a survey question that is likely to yield unbiased information?
A committee surveys public response to a plan to add bicycle lanes to downtown city streets. Describe a sampling method that can be used for each population.
8. bicyclists
9. car drivers

10. downtown business owners
11. Find the mean, variance, and standard deviation for the sample data set without using the statistical features of your calculator.
232 254 264 274 287 298 312 342 398 x
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Data x
 x
x
 x
2 s=_________ variance=____________
12 . Determine the whole number of standard deviations that includes all the data values for the sampling of students in a study group where the mean number of minutes spent studying for the College Algebra test is 66.1 minutes and the standard deviation is 3.1 minutes.
Data: 62 63 65 64 64 68 68 69 72 66
13. Use the data for average daily water usage of a family during the past 10 months. Find the mean and the standard deviation of the data. How many items in the data set fall within one standard deviation of the mean? Within two standard deviations?
124 gal 113 gal 152 gal 545 gal 150 gal
490 gal 442 gal 207 gal 124 gal 147 gal

14. Find the standard deviation for the sampling of times below. Make a comparison of the data using the standard
deviation. times of boys in 100-m dash state high-school finals in 1998
10.43 10.48 10.49 10.51 10.61 10.63 10.66 10.92
times of boys in 100-m dash state high-school finals in 2008
10.32 10.38 10.39 10.48 10.70 10.74 10.83 10.90
15.
In the previous lesson, an outlier is defined as a value “substantially different from the rest of the data in a set.” How could you use the concept of standard deviation to rewrite this definition?