1. The Minneapolis Star Tribune reported that 73% of American adults say that St

Question

1. The Minneapolis Star Tribune reported that 73% of American adults say that Starbucks coffee is overpriced. The source of this information was a national telephone survey of 1,000 American adults conducted by Rasmussen Reports. a. Construct a 95% confidence interval for p. i. (0.685 , 0.775) ii. (0.45 , 1) iii. (0.23 , 1) iv. (0.702 , 0.758) b. Interpret the 95% confidence interval for p. a. Given the sample results, do you think that the true proportion of American adults that say that Starbucks coffee is overpriced is greater than 0.75? a. Yes, the interval in a. contains 0.75. b. No, the interval in a. contains 0.75. c. Yes, the interval in a. does NOT contain 0.75. d. No, the interval in a. does NOT contain 0.75.

Explanation / Answer

here p= 0.73

and n=1000

hence std error =(p(1-p)/n)1/2 =0.014

for 95% CI ; z =1.96

therefore 95% confidence interval for p = estimated proportion -/+ z*std error = 0.702 to 0.758

threfore option ) iv. (0.702 , 0.758)

b. No, the interval in a. contains 0.75.

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.