The mean of the random variable X is the expected value E(X) of the number rolled with 2 dice. What is the mean of the random variable X? Show your work.

Question

anonymous · Answer

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anonymous · Answer

The attachment is the full question

zepdrix · Answer

Hey,

$\Large\bf \color{#008353}{\text{Welcome to OpenStudy! :)}}$

I'm not very good with probability...
gimme minute, see if I can make sense of this.

zepdrix · Answer

Do you need to answer the question before part 1?
Or we just do the parts?

anonymous · Answer

i think all of it but i dont even know what im reading so you probably know better

zepdrix · Answer

The table is pretty straight forward:
`x` is the given value rolled on the dice.
`P(x)` is the probability that the given value is rolled.

So for example when x=2,
The only way to roll 2 on a pair of dice is by rolling a 1 and a 1, yes?
Better known as snake eyes :)
That is only one combination that can roll a 2.

So the odds of rolling a 2 is 1 out of the total number of combinations.
1 out of 36.

They did all of that work for us though ~ they already calculated the odds for each number rolled, which is nice.

zepdrix · Answer

So all we need to do for part 1 is multiply the x value by it's probability

anonymous · Answer

o ok that makes sense

anonymous · Answer

second one is 6/36?

zepdrix · Answer

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