Question

you are operations manager for an airline and you are considering a higher fare level for passenger in aisle seats.how many randomly selected air passengers must you survey? assume that you want to be 99% confidence that the sample percentage is within 1.5 percentage points of the true population percentage

Answer 1

Solution:

E = 1.5% = 0.015

c = 99% = 0.99

= 1 - - 0.99 = 0.01

  /2 = 0.005

Using Z table ,

= 2.576

p is unknown.

Take p = 0.5

1 - p = 1 - 0.5 = 0.5

The sample size for estimating the proportion is given by

n =

= (2.576)² * 0.5 * 0.5 / (0.015²)

= 7373.08444444

= 7374 ..(round to the next whole number)

Required sample size is 7374