A random sample of 150 mortgages in the state of Mississippi was randomly selected. From this sample, 17 were found to be delinquent on their current payment. Calculate the 98% confidence interval estimate of the proportion of Mississippi mortgages that are delinquent. A random sample of 150 mortgages in the state of Mississippi was randomly selected. From this sample, 17 were found to be delinquent on their current payment. Calculate the 98% confidence interval estimate of the proportion of Mississippi mortgages that are delinquent.

Respuesta :

Answer:

98% confidence interval estimate of the proportion of Mississippi mortgages that are delinquent lie between ( 0.0529 , 0.1731 ) or 5.29% to 17.31%

Step-by-step explanation:

Given -

A random sample of 150 mortgages in the state of Mississippi was randomly selected. From this sample, 17 were found to be delinquent on their current payment.

Sample size n = 150

Let x be the no of people delinquent on their current payment

Proportion of sucess [tex](\widehat{p})[/tex] = [tex]\frac{x}{n}[/tex] =     [tex]\frac{17}{150}[/tex] = 0.113

confidence interval = 99%

[tex]\alpha = 1- \frac{98}{100}[/tex] = .02

[tex]z_{\frac{\alpha }{2}}[/tex] = [tex]z_{\frac{.02}{2}}[/tex] = 2.326

98% confidence interval estimate of the proportion of Mississippi mortgages that are delinquent = [tex]\widehat{p}\pm z_{\frac{\alpha }{2}}\frac{\sqrt{\widehat{p} (1 - \widehat{p})}}{n}[/tex]

                                                   = [tex]0.113\pm z_{\frac{.02 }{2}}\frac{\sqrt{0.113 (1 - 0.113)}}{150}[/tex]

                                                    = [tex]0.113\pm 2.326\times.02584[/tex]

                                                     = [tex]0.113\pm .06010[/tex]

                                                     = [tex](0.113 - .06010) , (0.113 + .06010)[/tex]

                                                      = ( 0.0529 , 0.1731 )