Which of the following is definitely true for mutually exclusive events A and B?
a. P(A) = 1 P(B)
b. P(A) + P(B) = 1
c. P(A and B) = P(A)P(B)
d. P(A and B) = 0
Q. 2What is the fundamental rule for data inference, or what property must samples have before valid inferences can be made about the population?
Q. 3For each of the following statements, determine if they are true or false. If events D and E are known to be mutually exclusive, then P(DE) = 0.
a. True
b. False
Q. 4A randomly selected sample of 400 students at a university with 15-week semesters was asked whether or not they think the semester should be shortened to 14 weeks (with longer classes). Forty-six percent of the 400 students surveyed answered yes. If the sample consisted of 300 students instead of 400 students, but the sample proportion of students who answered yes to the question was still 46, would the margin of error be smaller or larger?
Q. 5For each of the following statements, determine if they are true or false. If events A and B are known to be independent and P(A) = 0.2 and P(B) = 0.3, then P(A and B) = 0.5.
a. True
b. False
Q. 6A randomly selected sample of 400 students at a university with 15-week semesters was asked whether or not they think the semester should be shortened to 14 weeks (with longer classes). Forty-six percent of the 400 students surveyed answered yes. If the sample proportion of students who answered yes to the question was 36 instead of 46, would the margin of error be smaller or larger?
Quick Reply
