Help me answer this Please. The random variable X is the number of people who have a college degree in a randomly selected group of four adults from a particular town. Its probability distributions is given in the table.
X P (X=x)
0 0.0256
1 0.1536
2 0.3456
3 0.3456
4 .01296

Question

Help me answer this Please. The random variable X is the number of people who have a college degree in a randomly selected group of four adults from a particular town. Its probability distributions is given in the table.
X	P (X=x)
0	0.0256
1	0.1536
2	0.3456
3	0.3456
4	.01296

mathmale · Answer

Nice job of presenting this much of the problem statement.  However, this statement is not complete.  What were you asked to do?

anonymous · Answer

sorry your right it says Find  the expected value of the random variable.

mathmale · Answer

Have you done this kind of problem before?

This situation has five possible outcomes:  {0, 1, 2, 3, 4}.
The probability of each is given in the table.
Can you remember, or can you find, an explanation of how you find the mean or expected value of this situation?

anonymous · Answer

the answer is 2.40 but how was it done?

mathmale · Answer

That's what I'm asking you.

You are given the 5 possible outcomes (which I've listed), as well as the probability of each of thse outcomes.  What do you do with this information, mathematically, to obtain the expected value, 2.40?

Look up "expected value of a discrete random variable" and see what shows up.

anonymous · Answer

ok thanks

mathmale · Answer

One result I obtained myself was https://onlinecourses.science.psu.edu/stat200/node/36

mathmale · Answer

Look at the formula and try to explain to me what you have to do mathematically to obtain the expected value.

mathmale · Answer

What does this mean?$$x _{i}*P(x _{i})?$$

mathmale · Answer

That ' I ' is a 'subscript.'

mathmale · Answer

Note that your $$x _{2}=1$$
What is the probability of that occurring?  In other words, what is P(x_2)?

mathmale · Answer

In other words, what is (1)(0.1536)?

mathmale · Answer

Hoping you'll respond.

anonymous · Answer

yup I got it thanks

mathmale · Answer

What's the expected value?

anonymous · Answer

I'm working it now

mathmale · Answer

OK.

anonymous · Answer

got it answered thanks for all your help

mathmale · Answer

Please note:  You have a typo in    4	.01296.      this line should read    4	.1296.

mathmale · Answer

Happy for your success!

mathmale · Answer

Welcome to OpenStudy!  Happy to be the first person you've encountered here.

anonymous · Answer

no that was suppose to have a line and it didn't come  through so  that's why it separated

anonymous · Answer

yes thank you

mathmale · Answer

Take care; see you again here on OpenStudy.

anonymous · Answer

ok