SOLUTION: Please help me solve these problems: Given the probability distribution of a random variable outcome: -2, 4, 10 probability: 0.80, 0.15, 0.05 3. Compute the expected value

Question 444189: Please help me solve these problems:
Given the probability distribution of a random variable
outcome: -2, 4, 10
probability: 0.80, 0.15, 0.05
3. Compute the expected value (one digit after decimal point).
4. Compute the variance (two digits after decimal point).
Answer by htmentor(1343) (Show Source): You can put this solution on YOUR website!
The expected value of a discrete random variable x is
where are the outcomes and are their probabilities
Using the values x = -2, 4, 10; p = 0.8, 0.15, 0.05, we get
E(x) = -2*0.8 + 4*0.15 + 10*0.05 = -0.5
The variance of a discrete random variable x is

So we have
= (-2 - -0.5)^2 + (4 - -0.5)^2 + (10 - -0.5)^2 = 10.35
RELATED QUESTIONS
Please help me solve this problem of probability. We throw two fair dice. Let Random... (answered by rothauserc)

What is the probability that a normal random variable has an outcome within 2 standard... (answered by solver91311)

What is the probability that a normal random variable has an outcome within 2 standard... (answered by Boreal)

Please help me solve this: find the probability distribution for the random variable... (answered by stanbon)

Can someone check my answers to these questions to tell me if I did the correctly. If... (answered by Boreal)

Q1 Suppose that the random variable X has the following cumulative distribution... (answered by robertb)

Can someone please help me to understand what to do with these two problems??? I am lost. (answered by stanbon)

please help me to solve this problem: Froma box containing 4 dimes and 2 nickels, 3... (answered by edjones)

Can you solve these problem? and can you explain how to do? 1.) How many possible... (answered by stanbon)