Answer:
a) 1 student
b) probability = .4457
Explanation:
let x = number of students who legitimately missed the exam
a) given that the percentage of students who legitimately missed the exam = 2%
and total number of students registered =40
the number of students expected to miss the exam would be = ?\frac{2%}{100%}*80 = 0.8
rounding off to the nearest student, only 1 student would miss the exam
b) the probability that the professor will not have to create a deferred exam will be;
since 2% is observed to miss the exam, the percentage that would not miss the exam will be 100%-2% =98%
the probabiity that the professor will not have to create a deferred exam is P[E(x)=0] = \frac{98}{100}^40 = .4457
n/b it is raised to 40 because there are 40 students