1.
(one point)
Consider the following random sample of
X
:
3, 7, 15, 8, 8, 9, 12, 13, 3, 7, 5, 11, 9, 10, 2, 7, 9, 6, 12, 8
Use the random sample to estimate
(
29
E X
and
(
29
8
12
P
X

.
)
12
8
(
≤
≤
X
P
2
1
20
10
20
2
20
1
20
1
20
3
20
3
=
=
+
+
+
+
2. (two points)
Consider the Tuesday data only of the file
Daily Sales Alt.xls
.
Let
T
be the
continuous random variable that represents the gross sales amount on a Tuesday.
(
i
) Find the
value of
)
000
,
4
(
T
F
.
(
ii
) Use the sample to estimate
(
29
$4,000
$6,000
P
T

.
)
000
,
4
(
T
F
=
100
1
(
29
$4,000
$6,000
P
T

everything is below 6000 hence 1
)
000
,
4
(
T
F
=
100
99
3
. (
two points)
Based on the same data as in the previous problem, create a graph that displays
an approximation of the
p.d.f.
,
T
f
.