LetX

be a random variable with the following probability distribution:

Valuex

ofX

P

=

X

x

400.10500.15600.10700.30800.20900.15

Find the expectation

E

X

and varianceVar

X

ofX

. (If necessary, consult alist of formulas.)

=

E

x

0.3

=

Var

X

1