The table below gives approximate probabilities for scoring 0, 1, 2, 3, or 4 runs in one inning of Major League Baseball. (Although it is possible to score more than 4 runs in one inning, the probability is very small, so it is ignored in this question.)

x

x

P

(

x

)

P(x)

00.7310.1220.0930.0440.02

Round solutions to three decimal places, if necessary.

Compute the sum of these probabilities:

P

(

x

)

=

P(x)=

Compute the mean number of runs per inning, using this probability distribution:

=

=

Compute the standard deviation of this probability distribution:

=

=