PROBABILITY CHECKPOINT 2
Step 1 of 1
Question 1 of 11 Points: 10 out of 10
A fair die is rolled 12 times. Consider the following three possible
outcomes:
6543216543
(i)
21
1111111111
(ii)
11
3621542516
(iii)
43
Which of the following is true?
The three outcomes are equally likely.
It is absolutely impossible to get sequence (ii).
(i) is more likely than (ii).
(iii) is more likely than (i) or (ii).
Both (C) and (D) are true.
Good job! The die is fair. This means that all faces have an equal probability of occurring on any
given roll (1/6). Since each roll is independent of the other rolls, the probability of the each of the
three sequences shown is the same, (1/6)12. So the three sequences are equally likely (or we could
say equally “unlikely” since each has such a small chance of occurring).
Question 2 of 11 Points: 10 out of 10
Let A and B be two disjoint events such that P(A) = .30 and P(B) = .60.
What is P(A and B)?
0.18
0.72
0.90
0
This study source was downloaded by 100000836546216 from CourseHero.com on 03-09-2022 07:59:10 GMT -06:00
https://www.coursehero.com/file/24686058/Probability-Checkpoint-2-testdocx/
, none of the above
Good job! If two events are disjoint, then by definition, the two events cannot happen together. The
probability of these two events happening together is denoted by P(A and B). If this is impossible,
then P(A and B) = 0.
Question 3 of 11 Points: 10 out of 10
The following probabilities are based on data collected from U.S. adults
during the National Health Interview Survey 2005-2007. Individuals are
placed into a smoking category based on whether they ever smoked 100
cigarettes (in their lifetime) and their behavior in the last 30 days.
Neve Forme Current Non- Current
r r daily Daily
Probabilit 0.57
0.215 0.04 0.169
y 6
Based on these data, what is the probability that a randomly selected U.S.
adult currently smokes?
0.209
0.169
0.04
0.0068
none of these
Good job! We want to find P( ‘current non-daily’ or ‘current daily’ ). Since these are disjoint events,
we can add the two probabilities. 0.04 + 0.169 = 0.209
Question 4 of 11 Points: 10 out of 10
In a population, 5% of the females have had a kidney stone. Suppose a
medical researcher randomly selects two females.
Let X represent the event “the first female has had a kidney stone.”
Let Y represent the event “the second female has had a kidney stone.”
Which of the following is true about the two events?
X and Y are independent.
This study source was downloaded by 100000836546216 from CourseHero.com on 03-09-2022 07:59:10 GMT -06:00
https://www.coursehero.com/file/24686058/Probability-Checkpoint-2-testdocx/
Step 1 of 1
Question 1 of 11 Points: 10 out of 10
A fair die is rolled 12 times. Consider the following three possible
outcomes:
6543216543
(i)
21
1111111111
(ii)
11
3621542516
(iii)
43
Which of the following is true?
The three outcomes are equally likely.
It is absolutely impossible to get sequence (ii).
(i) is more likely than (ii).
(iii) is more likely than (i) or (ii).
Both (C) and (D) are true.
Good job! The die is fair. This means that all faces have an equal probability of occurring on any
given roll (1/6). Since each roll is independent of the other rolls, the probability of the each of the
three sequences shown is the same, (1/6)12. So the three sequences are equally likely (or we could
say equally “unlikely” since each has such a small chance of occurring).
Question 2 of 11 Points: 10 out of 10
Let A and B be two disjoint events such that P(A) = .30 and P(B) = .60.
What is P(A and B)?
0.18
0.72
0.90
0
This study source was downloaded by 100000836546216 from CourseHero.com on 03-09-2022 07:59:10 GMT -06:00
https://www.coursehero.com/file/24686058/Probability-Checkpoint-2-testdocx/
, none of the above
Good job! If two events are disjoint, then by definition, the two events cannot happen together. The
probability of these two events happening together is denoted by P(A and B). If this is impossible,
then P(A and B) = 0.
Question 3 of 11 Points: 10 out of 10
The following probabilities are based on data collected from U.S. adults
during the National Health Interview Survey 2005-2007. Individuals are
placed into a smoking category based on whether they ever smoked 100
cigarettes (in their lifetime) and their behavior in the last 30 days.
Neve Forme Current Non- Current
r r daily Daily
Probabilit 0.57
0.215 0.04 0.169
y 6
Based on these data, what is the probability that a randomly selected U.S.
adult currently smokes?
0.209
0.169
0.04
0.0068
none of these
Good job! We want to find P( ‘current non-daily’ or ‘current daily’ ). Since these are disjoint events,
we can add the two probabilities. 0.04 + 0.169 = 0.209
Question 4 of 11 Points: 10 out of 10
In a population, 5% of the females have had a kidney stone. Suppose a
medical researcher randomly selects two females.
Let X represent the event “the first female has had a kidney stone.”
Let Y represent the event “the second female has had a kidney stone.”
Which of the following is true about the two events?
X and Y are independent.
This study source was downloaded by 100000836546216 from CourseHero.com on 03-09-2022 07:59:10 GMT -06:00
https://www.coursehero.com/file/24686058/Probability-Checkpoint-2-testdocx/
