Question

A random variable X has the following probability distribution:

then E(X)=....................

विकल्प

• 0.8

• 0.9

• 0.7

• 1.1

Answer 1

(a) 0.8 

X = x	-2	-1	0	1	2	3
P(x)	0.1	0.1	0.2	0.2	0.3	0.1

`E(X)=sumx_iP(x_i)`

=( -2) x 0.1 + ( -1) x 0.1+ 0 x 0.2 +1x 0.2+ 2 x 0.3 + 3 x 0.1

= - 0.2 - 0.1 + 0 + 0.2 + 0.6 + 0.3

=0.8