Download Unit 4 Review - Rancho High School

Unit 4 Review
Name:___________________________
Per._______
Read all of the questions carefully. All work must be shown under the appropriate problem to receive full
credit. (each problem is 2 points each unless specified) The test will be 30 pts. total
1. A sample of 100 female politicians was asked, “Which ice cream flavor do you prefer: Chocolate or
Vanilla?” The respondents were classified by their political parties: Party X or Party Y. The results are
shown in the table below.
Flavor Preference
Chocolate Vanilla Total
Party X
?
40
Political
Party Y
30
60
Party
Total
35
65
100
If ice cream flavor preference is independent of political party, how many female politicians are in Party X
and prefer vanilla?
2. When looking at the association between the events “owns a car” and “owns a pet,” if the events are
independent, then the probability
P(owns a pet | owns a car)
is equal to _____.
3.
Chris is taking two classes this semester, English and American History. The probability he passes
English is 0.60 and the probability he passes American History is 0.40. The probability that he passes
either class is 0.90. What is the probability that he passes both classes?
4. The probabilities an adult male has high blood pressure and/or high cholesterol are given below.
Blood pressure
High Normal
High
0.10
0.20
Cholesterol
Normal 0.15
0.55
What is the probability of:
a. A man known to have high blood pressure also has high cholesterol.
b. A man known to have high cholesterol also has high blood pressure.
5. The probabilities an adult male has high blood pressure and/or high cholesterol are given below.
Blood pressure
High Normal
High
0.20
0.10
Cholesterol
Normal 0.25
0.45
What the probability a randomly selected adult male has high blood pressure or high cholesterol?
6. If P(A and B) = 0.6 and P(B) = 0.3, then P (A | B) = __________
7. If P (B | A) = 0.3 and P(A) = .4, then P(A and B) = __________
8. Two independent events, A and B are independent, have the following probabilities.
P  A  0.3
P  B   0.4
Compute:
1. P  A and B  __________
2. P  A or B 
__________
3. P  not A 
__________
4.
__________
P (A|B)
9. Below is a table of past record giving probability data for an ice cream and Gatorade sales at soccer and hockey
games. (1 point each)
Soccer Game
Hockey Game
Totals
Ice Cream
30
20
Gatorade
35
15
Totals
Leave answers in fraction form.
__________a) What is the probability that
an item is sold at a soccer game?
__________e) What is the probability that an item
was sold at a soccer game or a hockey game?
__________b) What is the probability that a
Gatorade was sold?
__________f) What is the probability that a
Gatorade was sold given that an item was sold at a
hockey game?
__________c) What is the probability that a
Gatorade was sold at a soccer game?
__________d) What is the probability that a
Gatorade was sold, given that the item was
sold at a soccer game?
__________g) What is the probability that the item
sold was not an ice cream?
__________h) What is the probability that the item
is not sold at a soccer game?
Answers
1. 35
2. P(owns a pet)
3. 0.1
4. a. 2/5 or 0.4
b. 1/3 or .333
5. 0.55
6. 2
7. 0.12
8. 0.12, 0.58, 0.7, 0.3
9. a. 65/100
b. 50/100
c. 35/100
d. 35/65
e. 100/100
f. 15/35
g. 50/100
h. 35/100