Unformatted text preview: placement when the player is in random-selection mode. Explain why this distinction is not important
for the construction of the interval in part (a). 5. An advertising agency in a large city is conducting a survey of adults to investigate whether there is an
association between highest level of educational achievement and primary source for news. The company
takes a random sample of 2,500 adults in the city. The results are shown in the table below. Primary Source
Total HIGHEST LEVEL OF EDUCATIONAL ACHIEVEMENT
High School Graduate
But Not College
2,500 (a) If an adult is to be selected at random from this sample, what is the probability that the selected adult is a
college graduate or obtains news primarily from the internet?
(b) If an adult who is a college graduate is to be selected at random from this sample, what is the probability that
the selected adult obtains news primarily from the internet?
(c) When selecting an adult at random from the sample of 2,500 adults, are the events “is a college graduate”
and “obtains news primarily from the internet” independent? Justify your answer.
(d) The company wants to conduct a statistical test to investigate whether there is an association between
educational achievement and primary source for news for adults in the city. What is the name of the
statistical test that should be used?
What are the appropriate degrees of freedom for this test? © 2010 The College Board.
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-8- 2010 AP® STATISTICS FREE-RESPONSE QUESTIONS (Form B)
Spend about 25 minutes on this part of the exam.
Percent of Section II score—25
Directions: Show all your work. Indicate clearly the methods you use, because you will be scored on the
correctness of your methods as well as o...
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- Spring '13
- AP Statistics, Simple random sample, AP® STATISTICS FREE-RESPONSE, STATISTICS FREE-RESPONSE QUESTIONS