Statistics and probability

Question

a programmer plans to develop a new software system. in planning for the operating system that he will use, he needs to estimate the percentage of computers that use a new operating system. how many computers must be surveyed in order to be 90% confident that his estimate is in error by no more than one percent complete parts (a) through (c) below.

Answer 1

Margin of error for a 90% confidence interval =

+/- 1.64 √ p(1-p)/n

If you don't have an estimate for p, use p = 0.5

So you need to solve 1.64 √[ p(1-p)/n] = 0.01

p = 0.5