Find the sample needed to estimate the percentage of adults who have consulted fortune tellers. Use a 0.03 margin error, use the confidence level of 98%, and use results from a prior Pew Research Center poll suggesting that 15% of adults have consulted fortune tellers.

Respuesta :

Answer: 766

Step-by-step explanation:

Given : The proportion of adults have consulted fortune tellers : p=0.

Margin of error : E= 0.03

Significance level :[tex]\alpha=1-0.98=0.02[/tex]

Critical value : [tex]z_{\alpha/2}=2.326[/tex]

The formula to calculate sample size ( if proportion is known) :-

[tex]n=p(1-p)(\dfrac{z_{\alpha/2}}{E})^2\\\\\Rightarrow\ n=(0.15)(1-0.15)(\dfrac{(2.326)}{0.03})^2\\\\\Rightarrow\ n=766.4557\approx766[/tex]

Hence, the required minimum sample would be 766.