HELP!!!!

[Buckshot]

Ok all you math geeks, I need a little help. I have an extra credit question for homework and I'm having trouble with it.

A fair die is tossed. If it turns up 5 or 6, you win $2. Otherwise, you win nothing. Let x be the amount you win in one play of the game and X (x-bar) the average you win in two plays of the game. Give the sampling distribution of the sample mean, X (x-bar).

I know this is a probability distrubution and it's early stat stuff, but I've forgotten it (it's been 10 years, sheesh, gimme a break) and now I'm stuggling with this one problem! Please help!

~stephen

[Homer]

One Play

2/6 of the time you win $2.

1/6 of the time you win $0.

On average, you win $.666. [(2/6)*2 + (1/6)*0]

Two Plays

16/36 of the time you win $0. [(4/6)^2]

4/36 of the time you win $4. [(2/6)^2]

16/36 of the time you win $2. [1 - (16/36) - (4/36)]

On average you win $1.333. [(16/36)*0 + (4/36)*4 + (16/36)*2 -- this is twice the average you win from a single spin]

I don't know if I've answered your question, but hopefully this will be of some help.

-- Homer

[Warik]

[ QUOTE ]
One Play

2/6 of the time you win $2.

1/6 of the time you win $0.

On average, you win $.666. [(2/6)*2 + (1/6)*0]

[/ QUOTE ]

Actually 4/6 of the time he wins $0 - not 1/6. You are wrong your whole calculation is messed up MUAHAHAAHAHAHHAHAHAHAHAHAHAHA!!!! The correct answer is [(2/6)*2 + (4/6)*0] = $.666!!!!

Don't worry. I won't tell anybody. /images/graemlins/grin.gif /images/graemlins/grin.gif /images/graemlins/grin.gif /images/graemlins/grin.gif /images/graemlins/grin.gif

[Buckshot]

Yes, you are correct but all his other figures are correct so it doesn't really matter he fat fingered the keyboard!

~stephen

[Homer]

Yes, it's 4/6. Don't know why I wrote 1/6, and twice for that matter.

[Buckshot]

In case you wanted to know:

X (x-bar) | P(x)
------------------------
0 | .444
.50 | .444
1.00 | .111


The question asks for the average you win that's why X (x-bar) is in money. Thanks, Homer, for you leading me down the correct path.

~stephen