Compute the 90% confidence interval estimate for the population proportion, p, based on a sample size of 100 when the sample proportion, is equal to 0.40.
A) 0.3880, 0.0412)
B) (0.3930, 0.4070)
C) (0.3194, 0.4806)
D) (0.3886, 0.4114)

Question

Quizplus · Accepted Answer

The 90% confidence interval for a population proportion is calculated using the formula: p ± Z*(√(p(1-p)/n)), where Z is the Z-score for 90% confidence (approximately 1.645). For p = 0.40 and n = 100, the interval is (0.3194, 0.4806).

Compute the 90% Confidence Interval Estimate for the Population Proportion