Download P(x) - tcann

AP Statistics
Practice- Probability Distributions
and Expected Value
1.
Name:____________________________________
Date:_____________________________________
Does the following refer to a probability distribution? If so, determine the mean and standard deviation.
Which x-values, if any, would be considered unusual? Use the   2 process.
2
3
4
5
6
7
8
9
10 11 12
x
P(x) 1/36 2/36 3/36 4/36 5/36 6/36 5/36 4/36 3/36 2/36 1/36
2.
Here is a problem taken from the 1988 Chartered Financial Analysts examination, which people
working in finance need to pass to make lots of money. Assume that stock in the Anheuser-Busch
Companies, Inc., returns the following percentages. Determine the expected Annual Return Rate for
the Anheuser-Busch Companies.
Annual Return
Rate (x)
20%
50%
30%
Probability
(p(x))
.20
.30
.50
AP Statistics
Answer Key
Name:____________________________________
Date:_____________________________________
1.
It is a Probability Distribution because
 7
  2.415
  2  (2.17,11.83)
2.
x
20
50
30
p(x)
0.20
0.30
0.50
Total:

 p( x)  36 / 36  1
2 and 12 are considered unusual
x  p (x )
4
15
15
34
Therefore, in the long run, a stockholder will see an expected return of 34% on his/her investment.