A random sample of 1003 adult Americans was asked, "Do you think televisions are a necessity or a luxury you could do without?" Of the 1003 adults surveyed, 521 indicated that televisions are a luxury they could do without. Construct and interpret a 95% confidence interval for the population proportion of adult Americans who believe that televisions are a luxury they could do without out.

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Answer:

The  95% confidence interval is  [tex]0.503 < p < 0.535[/tex]

The  interpretation is that there is 95% confidence that the true population proportion lie within the confidence interval

Step-by-step explanation:

From the question we are told that

    The  sample size is n  =  1003

     The number that indicated television are a luxury is  k  =  521

Generally the sample mean is mathematically represented as

           [tex]\r p = \frac{k}{n}[/tex]

          [tex]\r p = \frac{521}{1003}[/tex]

         [tex]\r p = 0.519[/tex]

Given the confidence level is  95% then the level of significance is mathematically evaluated as

       [tex]\alpha = 100 - 95[/tex]

       [tex]\alpha = 5\%[/tex]

       [tex]\alpha = 0.05[/tex]

Next we obtain the critical value of [tex]\frac{ \alpha }{2}[/tex] from the normal distribution table, the value is  

          [tex]Z_{\frac{\alpha }{2} } = 1.96[/tex]

The  margin of error is mathematically represented as

           [tex]E = Z_{\frac{\alpha }{2} } * \sqrt{ \frac{\r p (1- \r p )}{n} }[/tex]

=>       [tex]E = 1.96 * \sqrt{ \frac{ 0.519 (1- 0.519 )}{1003} }[/tex]

=>       [tex]E = 0.016[/tex]

The  95%  confidence interval is mathematically represented as

       [tex]\r p -E < p < \r p +E[/tex]

=>   [tex]0.519 - 0.016 < p < 0.519 + 0.016[/tex]

=>    [tex]0.503 < p < 0.535[/tex]