Question

Is Starbuck's coffee overpriced? A survey of 1,000 American adults show that 65% believe that Starbucks coffee is overpriced.

Form a 92% Confidence Interval for the point estimate. Round your final answer to the thousandths place

Answer 1

The 92% Confidence Interval For Proportions

= 0.65, 1 - = 0.35, n = 1000

The Z critical (2 tail) for = 0.02, is 2.326

The Confidence Interval is given by ME, where

The Lower Limit = 0.65 - 0.035 = 0.615

The Upper Limit = 0.65 + 0.035 = 0.685

The 92% Confidence Interval is (0.615 , 0.685)