According to a polling​ organization, 24% of adults in a large region consider themselves to be liberal. A survey asked 200 respondents to disclose their political​ philosophy: Conservative,​Liberal, And Moderate. Treat the results of the survey as a random sample of adults in this region. Do the survey results suggest the proportion is higher than that reported by the polling​organization? Use an alpha equals0.05 level of significance.75- Liberal65- Moderate61- Conservative

Respuesta :

Answer:

[tex]z=\frac{0.375 -0.24}{\sqrt{\frac{0.24(1-0.24)}{200}}}=4.47[/tex]  

Now we can calculate the p value based on the alternative hypothesis with this probability:

[tex]p_v =P(z>4.47)=0.00000391[/tex]  

The p value is very low compared to the significance level of [tex]\alpha=0.05[/tex] then we can reject the null hypothesis and we can conclude that the true proportion of people liberal is higher than 0.24

Step-by-step explanation:

Information given

n=200 represent the random sample taken

X=75 represent the number of people Liberal

[tex]\hat p=\frac{75}{200}=0.375[/tex] estimated proportion of people liberal

[tex]p_o=0.24[/tex] is the value that we want to test

z would represent the statistic

[tex]p_v[/tex] represent the p value

Hypothesis to test

We want to verify if the true proportion of adults liberal is higher than 0.24:

Null hypothesis:[tex]p \leq 0.24[/tex]  

Alternative hypothesis:[tex]p > 0.24[/tex]  

The statistic is given by:

[tex]z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}}[/tex] (1)  

Replacing the info given we got:

[tex]z=\frac{0.375 -0.24}{\sqrt{\frac{0.24(1-0.24)}{200}}}=4.47[/tex]  

Now we can calculate the p value based on the alternative hypothesis with this probability:

[tex]p_v =P(z>4.47)=0.00000391[/tex]  

The p value is very low compared to the significance level of [tex]\alpha=0.05[/tex] then we can reject the null hypothesis and we can conclude that the true proportion of people liberal is higher than 0.24