1. The table below gives all possible values of the random variable X and their respective probabilities, P(X). Calculate the mean of the random variable, X. Do not round your answer.

X	P(X)
0	0.10
2	0.30
7	0.45
12	0.15

a) 4.5

b) 0.5

c) 5.25

d) 5.55

2. Compute the standard deviation of the discrete probability distribution. Round to two decimal places.

X	P(X)
-5	0.5
-4	0.1
0	0
2	0.22
6	0.10
7	0.08

3. In the discrete probability distribution below, calculate the value of :

X	P(X x)
0	0.05
1	0.15
2	0.35
3	0.45
4	0.79
5	1

a) 0.25

b) 0.45

c) 0.10

d) 0.35

4. In the discrete probability distribution below, calculate the value of :

X	P(X)
0	0.2
1	0.1
2	0.3
3	0.15
4	0.18
5	0.07

a) 0.6

b) 0.15

c) 0.25

d) 0.75