SOLUTION: Suppose a discrete random variable X has a probability density function given by: x 3 5 7 8 9 10 12 16 P(X=x) 0.08 0.10 0.16 0.25 0.20 0.03 0.13 0.05 (Note: The probabilities

Algebra ->  Probability-and-statistics -> SOLUTION: Suppose a discrete random variable X has a probability density function given by: x 3 5 7 8 9 10 12 16 P(X=x) 0.08 0.10 0.16 0.25 0.20 0.03 0.13 0.05 (Note: The probabilities       Log On


   



Question 1132397: Suppose a discrete random variable X has a probability density function given by:
x 3 5 7 8 9 10 12 16
P(X=x) 0.08 0.10 0.16 0.25 0.20 0.03 0.13 0.05
(Note: The probabilities add to one. Any value x which is not in the table has probability zero.)
a) Calculate P(X > 9)
b) Calculate P(X is bigger than or equal to 9)
c) Calculate P(5 < X is smaller than or equal to 10)
d) Calculate the expected value of X, E(X)

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
P(x>9) includes the last 3, and their sum is 0.21
P(x>=9) includes the last 4, and that sum is 0.41
P(5 E(X)=sum of
3(0.08)=0.24
5(0.10)=0.50
7(0.16)=1.12
8(0.25)=2
9(0.20)=1.8
10(0.03)=0.3
12(0.13)=0.156
16(0.05)=0.8
That sum is 6.916