In a sample of 28 houses in a city 7 contained lead paint Cr

In a sample of 28 houses in a city, 7 contained lead paint. Create a 90% confidence interval estimate for the proportion of houses in that city containing lead paint. Use formulas & chart.

Solution

Sample X N Sample p 90% CI
1 7 28 0.250000 (0.115399, 0.384601)

Using the normal approximation.