Question

you are the operations manager for an airline and you are considering a higher fare level foer passengers in aisle seats. how many randomly selected passengers must you survey? assume that a prior survey suggest that about 43% of air passengers prefer aisle seat. assume that you want to be 87% confident that the sample percentage is within 2.8 percentage points of the tru population percentage.

Answer 1

Solution:

Given,

p = 43% = 0.43

1- p = 1 - 0.43 = 0.57

E = 2.8% = 0.028

c = 87% = 0.87

Now,

= 1 - c = 1 - 0.87 = 0.13

/2 = 0.065

= 1.514 (using z table)

The sample size for estimating the proportion is given by

n =

= (1.514)² * 0.43 * 0.57 / (0.028²)

= 716.60

= 717 ..(round to the next whole number)

Answer : Required Sample size is n = 717