Question

The following table shows the probability distribution for a discrete random variable.

X 13| 16 |17| 21| 23| 25 |26 |31
P(X) 0.07 |0.21| 0.17| 0.25| 0.05| 0.04| 0.13| 0.08
What is the mean of this discrete random variable. That is, what is E(X), the expected value of X?

Answer 1

Answer: APEX- 20.42

Step-by-step explanation: Multiply 13 by 0.07, multiply 16 by 0.21, and so on. then add up all of the decimals and that is your answer

Answer 2

X | 13 | 16 | 17| 21| 23| 25 | 26 | 31| |
------------|-----------------------------------------------------------------|.
P(X) | 0.07 | 0.21| 0.17| 0.25| 0.05| 0.04| 0.13| 0.08 |
------------|-----------------------------------------------------------------|
X.P(X) | 0.91 | 3.36| 2.89| 5.25| 1.15| 1.00| 3.38| 2.48 |
------------|-----------------------------------------------------------------|

E(X) = ∑(X.P(X) =(0.91+3.36+2.89+ 5.25+ 1.15+ 1.00+ 3.38+ 2.48)

E(X) = ∑(X.P(X) = 20.42

Pls review the calculation to be on the safe side