X
1
2
3
4
P(X)
1
8
2
8
3
8
2
8
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 566
MATHEMATICS
Y
–1
0
4
5
6
P(Y)
1
8
2
8
3
8
1
8
1
8
Clearly
E(X) =
1
2
3
2
22
1
2
3
4
2 75
8
8
8
8
8
× + ×
+ × + ×
=
=
and
E(Y) =
1
2
3
1
1
22
1
0
4
5
6
2 75
8
8
8
8
8
8
− × + ×
+ × + × =
× =
=
The variables X and Y are different, however their means are same It is also
easily observable from the diagramatic representation of these distributions (Fig 13