Out of 200 people sampled, 174 had kids Based on this, construct a 90% confidence interval for the true population proportion of people with kids. Give your answers as decimals, to three places

Respuesta :

Given:

Out of 200 people sampled, 174 had kids Based on this, construct a 90% confidence interval for the true population proportion of people with kids.

Required:

We need to find the confidence interval.

Explanation:

The proportion of the mean is

[tex]\frac{174}{200}=0.87[/tex]

The standard error of the sample is

[tex]\sqrt{0.87\times\frac{(1-0.87)}{200}}=0.02378[/tex][tex]\text{alpha\lparen}\alpha\text{\rparen is }1-\frac{90}{100}=0.10[/tex][tex]\text{ critical probability }(P^*)=1-\frac{\alpha}{2}=0.95[/tex]

Assuming a normal distribution, look for the z-score associated with a 0.95 cumulative probability.

z-score = 1.645

[tex]Margin\text{ of error =1.645}\times0.0238=0.0395[/tex]

The confidence interval is 0.87+0.0395 and 0.87-0.0395.

[tex]0.8305

Final answer:

[tex]0.8305