For a sample of 200 patients diagnosed with allergies, 25 were men. What is the 90% confidence interval for the population proportion? I set this up and got the answer of .087 -.16. The book has .091-.17. Could use help---I must be missing something.

Question

For a sample of 200 patients diagnosed with allergies, 25 were men. What is the 90% confidence interval for the population proportion?  I set this up and got the answer of .087 -.16.  The book has .091-.17.  Could use help---I must be missing something.

PsyDAG · Answer

What is the confidence interval for? Allergies? Gender? Both? Have you omitted some data? Mean? Standard deviation?

Lori · Answer

Actually that is the question given to me (only that info). I used the formula for the confidence interval for a proportion where you have to find the sample proportion. I used both 1.65 and 1.645 but to no avail to get that answer.