Probability

Question 0

P(AnB) =

Answer 0

Both A and B occur

So just intersection

Question 1

P(AuB) =

Answer 1

Either A, B or both occur

So intersection as well as singularly A and B

Question 2

P(A’) =

Answer 2

Everything except event A (so not intersection and not event A alone)

Question 3

How do you work our P(A’)?

Answer 3

1 - P(A)

Question 4

How do you work out the intersection (P(AuB))?

Answer 4

P(A) + P(B) - P(AnB)

• GIVEN THIS FORMULA •

Question 5

How do you work out P(A|B)?

Answer 5

P(B)

Question 6

Events are mutually exclusive if…

Answer 6

P(AnB) = 0

Question 7

Events are independent if…

Answer 7

P(A|B)  = P(A)              OR
P(B|A)  = P(B)              OR 
P(AnB) = P(A) * P(B)

Question 8

What is the sample space?

Answer 8

Set of all possible of outcomes of an experiment