Question

In a sample of 505 new websites registered on the Internet, 26 were anonymous (i.e., they shielded their name and contact information).

(a) Construct an exact 95 percent confidence interval for the proportion of all new websites that were anonymous. (Round your answers to 4 decimal places.)

Answer 1

Given that,

n = 505

x = 26

Point estimate = sample proportion   

At 95% confidence level the z is,

= 1 - 95%

= 1 - 0.95 = 0.05

/ 2 = 0.025

Z/2 = 1.96

Margin of error

  

A 95% confidence interval for population proportion p is ,

- E < p < + E

0.0515 - 0.0193 < p < 0.0515 + 0.0193

0.0322 < p < 0.0708

The 95% confidence interval for the population proportion p is ( 0.0322, 0.0708 )