Ask question
Question

# Explain the rules 3 and 4 in sum of several random variables.

Random variables
ANSWERED
asked 2021-01-13
Explain the rules 3 and 4 in sum of several random variables.

## Answers (1)

2021-01-14

Sums of Random Variables:
Rule 3: $$\mu_{x+y} = \mu_{x} + \mu_{y}$$
The rule 3 represents the mean values of the two random variables X and Ycan be added.
Rule 2: $$\sigma_{x+y}=\sqrt{\sigma_{x}^{2}+\sigma_{y}^{2}}$$
The rule 4 represents the standard deviation value of the random variable X+Y of the two random variables X and Y, the variance of the variables XYand Ycan be added if the variables are independent.

expert advice

...