A statistics instructor wishes to find out the relationship between the classification of a student and the student's grade in the course. the following is a breakdown of three sections of an introductory statistics course:
| Grade |
Freshman |
Sophmore |
Junior |
Senior |
| A |
0 |
8 |
9 |
10 |
| B |
0 |
6 |
8 |
11 |
| C |
1 |
7 |
9 |
12 |
| D |
2 |
4 |
1 |
4 |
| F |
0 |
6 |
2 |
1 |
| Total |
3 |
31 |
29 |
38 |
a) What is the probability that the student is a junior and makes a B in the course?
B) What is the probability that the student does not make a A in the course, given the student is a senior?
C) What is the probability that the student makes a D or F in the course?
D) Let A be the event that a sophmore is taking the course. Let B be the even that the student makes a C in the course. Are these events A and B independent? Are the events A and B mutally exclusive?