STAT 400
Examples for 01/21/2011
Spring 2011
1.
Suppose a 6-sided die is rolled.
The sample space,
S
, is
{
1, 2, 3, 4, 5, 6
}
.
Consider the following events:
A =
{
the outcome is even
}
,
B =
{
the outcome is greater than 3
}
,
a)
List outcomes in
A,
B,
A
'
,
A
∩
B,
A
∪
B.
A =
{
the outcome is even
}
=
{
2, 4, 6
}
,
B =
{
the outcome is greater than 3
}
=
{
4, 5, 6
}
,
A
'
=
{
1, 3, 5
}
,
A
∩
B =
{
4, 6
}
,
A
∪
B =
{
2, 4, 5, 6
}
.
b)
Find the probabilities
P(
A
),
P(
B
),
P(
A
'
),
P(
A
∩
B
),
P(
A
∪
B
)
if the die is balanced (fair).
P( A ) =
3
/
6
,
P( B ) =
3
/
6
,
P( A
'
) =
3
/
6
,
P( A
∩
B ) =
2
/
6
,
P( A
∪
B ) =
4
/
6
.