Question

Assume that a sample is used to estimate a population proportion p. Find the 99.5% confidence interval for a sample of size 99 with 26.3% successes. Enter your answer as an open-interval (i.e., parentheses) using decimals (not percents) accurate to three decimal places.

99.5% C.I. =

Answer should be obtained without any preliminary rounding. However, the critical value may be rounded to 3 decimal places.

Answer 1

We have given,              
              
      
n=99          
Estimate for sample proportion
Level of significance is =0.005      
Z critical value(using Z table)=2.807      
  
Confidence interval formula is              

=(0.139,0.387)      

99.5% C.I. = (0.139,0.387)