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Chapter 7: Probability
Figure 7-1:
Tree diagram for a two-child family
From
Figure 7-1
, if you follow along the “branches” of the tree, you will
trace out all the possible outcomes as listed on the right hand side. Thus, the
sample space is then
S
= {
BB
,
BG
,
GB
,
GG
}.
Example 7.3:
List the sample space for a three-child family.
Solution:
Let
B
represent the outcome of a boy and
G
for a girl. The tree
diagram in
Figure 7-2
depicts all the possible outcomes.