Unit 5 Probability

Question 1

Disjoint

Answer 1

Two events are disjoint when one or the other event can happen, but NOT both.

Question 2

Mutually Exclusive

Answer 2

Disjoint

Question 3

Probability is always a number between…

Answer 3

0 and 1

Question 4

Probability of at least one =

Answer 4

1 - P(None)

Question 5

Are A and B disjoint events? Why or why not?

Answer 5

No, because there is a middle which represents the probability of both A and B happening.

Question 6

What does the shaded area represent?

Answer 6

P(P and Q)

Question 7

What does the shaded area represent?

Answer 7

P(P or Q)

Question 8

What does the shaded area represent?

Answer 8

P(Q and not P)

Question 9

Independent Events

Answer 9

2 events are independent if one event does not influence or affect the outcome of the other event in any way.

Question 10

How do you find P(A or B)?

Answer 10

P(A) + (B) - P(A and B)

add and subtract the middle

Question 11

If 2 events A and B are independent, how can we find the middle, P(A and B)?

Answer 11

Multiply P(A) times P(B)

Question 12

If 2 events A and B are disjoint, how can we find the middle, P(A and B)?

Answer 12

P(A and B) will always be 0, because there is not overlap in disjoint events.

Question 13

How do we check for independence on a segmented bar chart?

Answer 13

Bars are different = dependent

Bars are the same = independent

Question 14

How do we check for independence in a contigency table?

Answer 14

Ratios in and outside of table are the same = independent.

Ratios different = dependent