The salespeople at Gold Key Realty sell up to 9 houses per month. The probability distribution of a salesperson selling x houses in a month is as follows: Sales (x) 0 1 2 3 4 5 6 7 8 9
Probability f (x) .05 .10 .15 .20 .15 .10 .10 .05 .05 .05
a. What is the mean for the number of houses sold by a salesperson per month?
b. What is the standard deviation for the number of houses sold by a salesperson per month?
c. Any salesperson selling more houses than the amount equal to the mean plus two standard deviations receives a bonus. How many houses per month must a salesperson sell to receive a bonus?