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View Full Version : Random sampling/Confidence intervals


willkin
Jul 8, 2009, 12:18 PM
a random sample of 20 pages of an textbook was made and 60% had drawings or figures on the. Find the 95% confidence interval for the actual proportion of pages on which a drawing or figure would be found?

galactus
Jul 8, 2009, 12:26 PM
Use the formula z\cdot \sqrt{\frac{pq}{n}}

The z score for a 95% CI is 1.96

p=.6 and q=.4 and n=20

Add to and subtract from the .60 to find the C.I.