In: Statistics and Probability
It is estimated that 30% of university students are taking five
or more classes this semester (let us call them full-load
students). Among the full-load students, 20% are working part-time.
On the other hand, among the non-full-load students, 60% are
working part-time.
a) When a university student is randomly selected, what is the probability that one is a full-load student and working part-time? [2]
Define event A as: university students taking five or more classes (or being full-load students).
Define event B as: university students working
part-time.
b) When a university student is randomly selected, what is the probability that one is working part-time but not taking full-load? [2]
It is estimated that 30% of the students are taking five or more classes this semester. They are full load students.
Among the full load students, 20% are working part time.
On the other hand, among the non full load students, 60% are working part time.
Now, let us define
A=University student being full load student.
B=University student working part time.
The information given is
Question (a)
We have to find the probability that a randomly selected student is a full load student and works part time.
So, basically we have to find
By the definition of conditional probability,
this is equal to
So, the answer is 0.06.
Question (b)
We have to find the probability that a randomly selected student is working part time but not taking full load.
So, basically we have to find
By the definition of conditional probability, this becomes
The answer is 0.42.