Problem:
A professor knows from past experience that the time for students to complete a quiz has an N(19, 3) distribution.
Requirement:
(i) If he allows 20 minutes for the quiz, what percent of the students will not complete the quiz?
(ii) Suppose that he wants to allow sufficient time so that 95% of the students will complete the quiz in the allotted time. How much time should he allow for the quiz?