Question

In a survey funded by the UW school of medicine, 750 of 1000 adult Seattle residents said they did not believe they could come down with a sexually transmitted infection (STI). Construct a 95% confidence interval estimage of the proportion of adult Seattle residents who don't believe they can contract an STI. (Use a z score of 1.96 for your computations.)

Answer 1

Answer:$\left ( 0.723,0.777\right )$

Step-by-step explanation:

Given

x=750

n=1000

Population proportion $\hat{p}=\frac{750}{1000}$

$\hat{p}=0.75$

For 95% confidence level z is given by

$\alpha =1-0.95$

$\frac{\alpha }{2}=0.025$

Error in estimation=$Z_{\frac{\alpha }{2}}\sqrt{\frac{\hat{p}\left (1-\hat{p} \right )}{n}}$

E=1.96$\sqrt{\frac{0.75\left (1-075\right )}{1000}}$

E=0.027

interval $\left ( 0.723,0.777\right )$