Question

You are the operations manager for an airline and you are considering a higher fare level for passengers in aisle seats. How many randomly selected air passengers must you​ survey? Assume that you want to be 90​% confident that the sample percentage is within 4.5 percentage points of the true population percentage. Complete parts​ (a) and​ (b) below.

a. Assume that nothing is known about the percentage of passengers who prefer aisle seats.

n=__________ ​(Round up to the nearest​ integer.)

b. Assume that a prior survey suggests that about 38​% of air passengers prefer an aisle seat.

n=______________ ​(Round up to the nearest​ integer.)

Answer 1

Given : Significance level=

Margin of error=E=0.045

Now , the critical value is , ; FromZ-table

a. Since , the percentage of passengers who prefer aisle seats is unknown.

Therefore , assume that =0.05

Therefore , the required sample size is ,

b. Since ,  =0.38

Therefore , the required sample size is ,