Respuesta :
Answer:
[tex]z=\frac{0.775 -0.73}{\sqrt{\frac{0.73(1-0.73)}{200}}}=1.433[/tex]
Now we can find the p value. Since we have a bilateral test the p value would be:
[tex]p_v =2*P(z>1.433)=0.152[/tex]
Since the p value is higher than the significance level of 0.1 we have enough evidence to FAIL to reject the null hypothesis and the best conclusion for this case would be:
Do Not reject H0
Step-by-step explanation:
Information provided
n=200 represent the sample size slected
X=155 represent the cell phone owners used text messaging
[tex]\hat p=\frac{155}{200}=0.775[/tex] estimated proportion of cell phone owners used text messaging
[tex]p_o=0.73[/tex] is the value to verify
[tex]\alpha=0.1[/tex] represent the significance level
We need to conduct a z test for a proportion
z would represent the statistic
[tex]p_v[/tex] represent the p value
System of hypothesis
We want to verify if the true proportion of cell phone owners used text messaging is different from 0.73 so then the system of hypothesis are:
Null hypothesis:[tex]p=0.73[/tex]
Alternative hypothesis:[tex]p \neq 0.73[/tex]
The statistic to check this hypothesis is given by:
[tex]z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}}[/tex] (1)
Replacing the data given we got:
[tex]z=\frac{0.775 -0.73}{\sqrt{\frac{0.73(1-0.73)}{200}}}=1.433[/tex]
Now we can find the p value. Since we have a bilateral test the p value would be:
[tex]p_v =2*P(z>1.433)=0.152[/tex]
Since the p value is higher than the significance level of 0.1 we have enough evidence to FAIL to reject the null hypothesis and the best conclusion for this case would be:
Do Not reject H0