Tree diagrams and tables

1
Tree diagrams and tables
A multistage event consists of 2 or more events
occurring together. Tables can display the
outcomes for 2 stage events. Tree diagrams can
display the outcomes for multistage events.

1. 4 2 8
2. See below

c) 4 d) P(prime)
4/8 ½
1 2 3 4
H H1 H2 H3 H4
T T1 T2 T3 T4
2
Example 2

• A woman has 3 children.
• What is the probability she has
• exactly 2 boys?
• at least 2 boys?
• More than 2 boys?

P(2B, 1G)
3/8
4/8
½
P(2B)
P(gt2B)
1/8
Child 3
Child 2
Child 1
BBB
?
?
?
BBG
?
?
?
BGB
?
?
?
BGG
?
?
?
GBB
?
?
?
GBG
?
?
?
?
?
?
GGB
?
?
?
GGG
3
Todays work
Exercise 7A pg 211 Q1, 2, 3, 5, 8, 9, 10