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 2.5 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= 1083

b.  Assume that a prior survey suggests that about 39​% of air passengers prefer an aisle seat.

n=____

Answer 1

Given : Margin of error=E=2.5%=0.025

Significance level=

The critical value is , ; From Z-table

a. Since , the estimate of the percentage of passengers who prefer aisle seats is not known.

Therefore , assume that =0.5

Therefore , the required sample size is ,

b. Since , the estimate of the percentage of passengers who prefer aisle seats is known and  =0.39

Therefore , the required sample size is ,