Probabilities and Statistics – Expected Values

Help me study for my Statistics class. I’m stuck and don’t understand.

Answer Questions #1-8. Do not need to show work.

1.Use the following Probability Model that represents the different amounts of money a player can win from a certain game. Use this Model for all questions on this review.

Outcome $0 $6 $10 $100

Probability 0.62 0.21 ? 0.04

Find the missing probability.

2. Find P($100).

3. Find P(~$0).

4. Find P($50).

5. Use the probability model and answer from problem #1 to find the expected value. Do not use the dollar symbol when entering your answer.

6. Find the expected value for the probability model shown below:

Outcome	– $8	$0	$10	$90
Probability	0.43	0.31	0.21	0.05

Enter your solution as a decimal (do not use the dollar symbol).

7. The probability model below is a little bit different. While you can not find the expected value from this table, you should be able to write two equations that must be true in the probability model. If you are told that the expected value is $0.40, which two equations must be true?

outcome	$4	– $2	$1	$19
probability	x	y	z	0.06

Select one:

4x – 2y + z = -0.74 AND x + y + z = 0.94

4x – 2y + z = 1.14 AND x + y + z = 0.06

4x – 2y + z = 0.74 AND x + y + z = -0.94

4x – 2y + z = -1.14 AND x + y + z = -0.06

8. If you know that the expected value for the following probability model is supposed to be $0.48, find the missing value in the table:

Outcome	– $5	-$2	?	$50
Probability	0.50	0.27	0.19	0.04

(do not use the dollar symbol).