1.2 Conditional Probability

Question 1

Conditional Probability

Answer 1

When knowing more information about experiment, the sample space gets smaller

Question 2

Is condiitonal probability more likely to happen or Uncondintional probability

Answer 2

Conditional, because the sample space is smaller

Question 3

How many stages in conditional probability

Answer 3

2 stages

Question 4

Given vs And

Answer 4

Given is restricting samples space

And is the original sample space

Question 5

Keywords conditiona probability

Answer 5

If given assuming knowing

Question 6

Two ways to solve conditional probabiltiy question

Answer 6

Contingency Table

Tree Diagram

Question 7

KEY THING TO NOTE ABOUT CONTINGENCY TABLES!!!

Answer 7

Is it a % of a subsect? You multiply by the subsect!!!!

Question 8

KEY THING ABOUT TREE DIAGRAMS

Answer 8

To get Intersection you must multiply both the first and second branches of your conditional probability

Question 9

How to go from Tree Diagram to Contingency Table

Answer 9

Multiply both branches! and then fill out using the COND PROB FORMULA

Question 10

P(AIB)

P(BIA)

Answer 10

=P(AnB)/P(B)
=P(BnA)/P(A)

Question 11

Independance

Answer 11

Knowing one event does not restrict the sample space of the other event

Question 12

if A and B independant then?

2 things

Answer 12

A times B= AnB

A and B are independant
A and Bcomp are indepent
Acomp and B are independant
Acomp and Bcomp are independant

Question 13

IF DEPENDANT

Answer 13

tHen A x B does not equal A n B

Question 14

How to use Contingency Tables with GIVEN this quesitons

Answer 14

1. Isolate a row/Column
2. Figure out N(A)
3. Divide by N(S)

Question 15

How to use Tree Diagrams to solve condiitonal

Answer 15

1. First branch is the condition
2. Second are not
3. Write out aas condiitonals for all four branches
4. Multiply branch 1 by 2 to get the intersection value

Question 16

a secret way to check

cont table

Tree diagram

Answer 16

Cont table all the centre cells should equal the outside cells

In tree diagrams, first branches should equal 1, each sub branch secto=ion equal 1, once caluclated all of intersection probabilites, all equal 1 too

Question 17

Independance vs Mutually Exclusive

Answer 17

P(AnB)= P(A) x P(B)

P(AnB) = 0

Knowing one doesnt change the prob of the other

vs. they have no
overlap!

Question 18

If given that info is independant

Answer 18

Then use P(A)xP(B)= P(AnB) LOGIC

Fill out ocont table and solve!