Question

A recent study of 600 Internet users in Europe found that 335 of Internet users were women. What is the 98% confidence interval estimate for the true proportion of women in Europe who use the Internet?

• A.

  0.511 to 0.605

• B.

  0.316 to 0.384

• C.

  0.567 to 0.769

• D.

  0.454 to 0.676

Answer 1

Solution :

Given that,

Point estimate = sample proportion = = x / n = 335 / 600 = 0.558

1 - = 1 - 0.558 = 0.442

Z/2 = 2.326

Margin of error = E = Z / 2 * (( * (1 - )) / n)

= 2.326 * (((0.558 * 0.442) / 600)

= 0.047

A 98% confidence interval for population proportion p is ,

- E < p < + E

0.558 - 0.047 < p < 0.558 + 0.047

0.511 < p < 0.605

The 98% confidence interval for the population proportion p is : 0.511 , 0.605

option A. is correct