Concept explainers
Choose the option that reveals the meaning of the phrase ±4%.
Answer to Problem 104SE
The correct answer is “It would be unlikely to get the observed sample proportion of 0.73 unless the actual proportion of cell phone users who want e-mail service is between 0.69 and 0.77”.
Explanation of Solution
Margin of error:
In a confidence interval, the margin of error (E) denotes the
Here, the margin of error is 4%. The confidence interval for the given scenario is as follows:
According to the definition of margin of error, it represents that the actual proportion of cell phone users who want e-mail service is between 0.69 and 0.77.
From the given options, option d conveys the correct meaning for the margin of error.
The correct answer is “It would be unlikely to get the observed sample proportion of 0.73 unless the actual proportion of cell phone users who want e-mail service is between 0.69 and 0.77”.
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Chapter 8 Solutions
Mathematical Statistics with Applications
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