A Researcher Wants to Estimate the Proportion of Manufacturing Companies

Multiple Choice

A researcher wants to estimate the proportion of manufacturing companies that use the six sigma method.For this purpose,she takes a random sample of 50 manufacturing companies and finds out that 28 of them employ this method.The 95% confidence interval for the proportion of manufacturing companies that use six sigma is ______.

A) 0.462 to 0.628
B) 0.452 to 0.638
C) 0.442 to 0.648
D) 0.432 to 0.658
E) 0.422 to 0.668