In: Statistics and Probability
What is the probability that a randomly selected CMSU student
will be male?
The Student News Service at Clear Mountain State University (CMSU)
has decided to gather data about the undergraduate students that
attend CMSU. CMSU creates and distributes a survey of 14 questions
and receives responses from 62 undergraduates
What is the probability that a randomly selected CMSU student
will be female?
Find the conditional probability of different majors among the male
students in CMSU.
Find the conditional probability of different majors among the
female students of CMSU.
Find the conditional probability of intent to graduate, given that
the student is a male.
Find the conditional probability of intent to graduate, given that
the student is a female.
Find the conditional probability of employment status for the male
students as well as for the female students.
Find the conditional probability of laptop preference among the
male students as well as among the female students.
ID | Gender | Age | Class | Major | Grad Intention | GPA | Employment | Salary | Social Networking | Satisfaction | Spending | Computer | Text Messages |
1 | Female | 20 | Junior | Other | Yes | 2.9 | Full-Time | 50 | 1 | 3 | 350 | Laptop | 200 |
2 | Male | 23 | Senior | Management | Yes | 3.6 | Part-Time | 25 | 1 | 4 | 360 | Laptop | 50 |
3 | Male | 21 | Junior | Other | Yes | 2.5 | Part-Time | 45 | 2 | 4 | 600 | Laptop | 200 |
4 | Male | 21 | Junior | CIS | Yes | 2.5 | Full-Time | 40 | 4 | 6 | 600 | Laptop | 250 |
5 | Male | 23 | Senior | Other | Undecided | 2.8 | Unemployed | 40 | 2 | 4 | 500 | Laptop | 100 |
6 | Female | 22 | Senior | Economics/Finance | Undecided | 2.3 | Unemployed | 78 | 3 | 2 | 700 | Laptop | 30 |
7 | Female | 21 | Junior | Other | Undecided | 3 | Part-Time | 50 | 1 | 3 | 500 | Laptop | 50 |
8 | Female | 22 | Senior | Other | Undecided | 3.1 | Full-Time | 80 | 1 | 2 | 200 | Tablet | 300 |
9 | Female | 20 | Junior | Management | Yes | 3.6 | Unemployed | 30 | 0 | 4 | 500 | Laptop | 400 |
10 | Female | 21 | Senior | Economics/Finance | Undecided | 3.3 | Part-Time | 37.5 | 1 | 4 | 200 | Laptop | 100 |
11 | Female | 23 | Senior | Economics/Finance | Yes | 2.8 | Full-Time | 50 | 2 | 5 | 400 | Laptop | 200 |
12 | Male | 21 | Senior | Undecided | No | 3.5 | Full-Time | 37 | 2 | 3 | 500 | Laptop | 100 |
We have a data set consisting of 12 entries. So for all purpose, the sample size is n(S) = 12. This will therefore be the denominator for all problems, unless sample size itself gets changed.
1. What is the probability that a randomly selected CMSU student will be male?
We observe there are 5 males. Hence, the probability is 5/12
2. What is the probability that a randomly selected CMSU student will be female?
Since the remaining 7 are female, hence the probability is 7/12
3. Find the conditional probability of different majors among the male students in CMSU.
Out of the 5 males, one is undecided. Among the remaining, there are three different majors - Management, CIS and Others.
P (Management | Male) = 1/5
P (CIS | Male) = 1/5
P (Other | Male) = 2/5
P (Undecided | Male) = 1/5
4. Find the conditional probability of different majors among the female students of CMSU.
Among the females, everyone is decided and we see Economics/Finance instead of CIS.
P (Management | Female) = 1/7
P (Economics/Finance | Female) = 3/7
P (Other | Female) = 3/7
5. Find the conditional probability of intent to graduate, given that the student is a male.
P (GradIntention Yes | Male) = 3/5
P (GradIntention No | Male) = 1/5
P (GradIntention Undecided | Male) = 1/5
6. Find the conditional probability of intent to graduate, given that the student is a female.
P (GradIntention Yes | Female) = 3/7
P (GradIntention Undecided | Female) = 4/7
7. Find the conditional probability of employment status for the male students as well as for the female students.
There are three different status: Part-Time, Full-Time and Unemployed
P (Part-Time| Male) = 2/5
P (Full-Time | Male) = 2/5
P (Unemployed | Male) = 1/5
P (Part-Time| Female) = 2/7
P (Full-Time | Female) = 3/5
P (Unemployed | Female) = 2/5
8. Find the conditional probability of laptop preference among the male students as well as among the female students.
Among the males, everyone prefers a laptop and among females, one prefers tablet instead of laptop.
P (Laptop | Male) = 1
P (Laptop | Female) = 6/7
P (Tablet | Female) = 1/7