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An unemployment office in a small town has developed the following probability

distribution for the number of new unemployment claims processed per week.

Number of

New Claims

4

5

6

7

8

9

10

Probability

.05

.10

.15

.20

.20

.20

.10

(a) What is the expected number of new unemployment claimsprocessed per week?

(b) What is the variance in the number of new unemployment claims processed per week?

(c) What is the standard deviation in the number of new unemployment claims processed per week?