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Chapter 10: Q. 15 (page 623)

As part of the Pew Internet and American Life Project, researchers surveyed a random sample of 800teens and a separate random sample of 400young adults. The teens, 79%said that they own an iPod or MP3 player. For the young adults, this figure was67%. Is there a significant difference between the population proportions? State appropriate hypotheses for a significance test to answer this question. Define any parameters you use

Short Answer

Expert verified

H0:p1-p2=0

Ha:p1-p2鈮�0

Step by step solution

01

Given Information

Given

p^1=79%=0.79

n1=800

p^2=67%=0.67

n2=400

02

Explanation

The null hypothesis states that the population proportions are equal or that their difference is zero:

H0:p1-p2=0

The alternative hypothesis states the opposite of the null hypothesis (according to the claim):

Ha:p1-p2鈮�0

p1is the population proportion of teens that own an iPod or MP3 player.

p2is the population proportion of young adults that own an iPod or MP3 player.

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