# statistics help

posted by
**Kim5**
.

The number of ships to arrive at a harbor on any given day is a random variable represented by x. The probability distribution of x is as follows. (Give your answers correct to two decimal places.)

x 10 11 12 13 14

P(x) 0.38 0.1 0.07 0.12 0.33

(a) Find the mean of the number of ships that arrive at a harbor on a given day.

(b) Find the standard deviation, รณ, of the number of ships that arrive at a harbor on a given day.