Question

Construct a confidence interval of the population proportion at the given level of confidence.

x=160, n=200, 99% confidence

The lower bound is:

The upper bound is:

Answer 1

We have given,          
          
x=160      
n=200      
Estimate for sample proportion=   0.8
Z critical value(using Z table)=2.58  
Confidence interval formula is  

=(0.727,0.873)  
          
Lower limit for confidence interval=0.727
          
Upper limit for confidence interval=0.873