Question

A clinical trial tests a method designed to increase the probability of conceiving a girl. In the study 560 babies were​ born, and 308 of them were girls. Use the sample data to construct a 99​% confidence interval estimate of the percentage of girls born. Based on the​ result, does the method appear to be​ effective?

___ < p < ___​(Round to three decimal places as​ needed.)

Answer 1

We have given,              
              
x=308          
n=560          
Estimate for sample proportion=0.55  
Level of significance is =1-0.99=0.01      
Z critical value(using Z table)=2.576      
              
Confidence interval formula is              


=(0.496, 0.604)

0.496<p<0.604