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 two percentage points? ​
a) Assume that nothing is known about the percentage of computers with new operating systems. n = 1691 (correct answer) ​