Answer:
The probability that the proportion of vegetarians in a sample of 471 Americans would be greater than 8% is P=0.776.
Step-by-step explanation:
We have to calculate a probability that a sample of n=471 has a proportion greater than 8%, given that the population proportion is 9%.
First, we have to calculate the parameters of the sampling distribution of the proportions:
[tex]\hat{p}=p=0.09\\\\\\\sigma_{\hat{p}}=\sqrt{\dfrac{p(1-p)}{n}}=\sqrt{\dfrac{0.09\cdot 0.91}{471}}=0.0132[/tex]
Now, we can calculate the probability using the z-score:
[tex]z=\dfrac{p-\hat{p}}{\sigma_{\hat{p}}}=\dfrac{0.08-0.09}{0.0132}=\dfrac{-0.01}{0.0132}=-0.7576[/tex]
Then, the probability is:
[tex]P(p>0.08)=P(z>-0.7576)=0.776[/tex]