In this week you will learn about the contingency table, union probability, joint probability, conditional probability and the test of independence.
Use the contingency table below to find the following probabilities.
| B | B’ |
A | 60 | 90 |
A’ | 70 | 50 |
a. P(A)
b. P(A’)
c. P(A and B)
d. P(A or B)
The employees of a company were surveyed and asked their educational background and marital status. Of the 600 employees, 400 had university degrees, 100 were single and 60 were singles with a degree.
a. Construct a contingency table for this problem.
b. Find the probability that a randomly selected employee of the company is single or has a university degree.
c. What percentage of single employees have university degrees?
d. Are marital status and educational background statistically independent? Explain.
At a certain university, 25% of students are in the business faculty. Of the students in the business faculty, 66% are males. However, only 52% of all students at the university are male.
a. What is the probability that a student selected at random in the university is a male in the business faculty?
b. What is the probability that a student selected at random in the university is male or is in the business faculty?
c. What percentage of males are in the business faculty?