AP Statistics
Midterm Exam Review
1.
5. The number of vehicles passing a tollgate
between 7 am and 8 am were recorded for
twenty different days.
Classify as qualitative or quantitative.
a.
b.
c.
d.
e.
10
46
20
married or not married
number of books in your locker
rocks divided into categories
weight of a rock
zip codes
a.
b.
c.
d.
e.
f.
g.
h.
2. Classify as Continuous or Discrete
a.
b.
c.
d.
weight of your books
number of tv’s you own
time it takes to run the 50
number of races won
we will survey every 5th person who
comes in the door.
b. Put all the names in a hat and draw out 5
names
c. We will survey everyone in two of the
schools out of the district
d. Survey the first 5 people I see because I
don’t have much time
e. Separate everyone according to eye color
and then choose 4 from each group.
a.
4. During July, a private pool recorded the
weights of 30 males in its water aerobics
class.
a.
156
171
158
157
172
125
156
170
160
158
166
165
163
169
162
159
166
136
32
33
12
15
27
22
16
15
30
22
16
41
31
19
Construct a stem & leaf
Find the mean
Find the median
Find the mode.
Construct the box plot
Find the variance
Find the standard deviation.
Are there any outliers? Show your work.
6. If x  6 , x  20 , and s  9 , what is the zscore. What does it mean?
3. Classify the type of sampling as being either
cluster, systematic, convenience, random, or
stratified.
143
142
138
173
138
120
26
27
16
167
164
164
160
159
168
7.
The diastolic blood pressure x, and the
systolic blood pressure, y, were recorded for
13 females.
x
y
76 70 82 90 68 60 62
122 102 118 126 108 130 104
x
y
60 62 72 68 80 74
118 130 116 102 122 120
a. Find the correlation coefficient.
b. Find the linear regression line.
c. What is the predicted value of y for
x = 65?
d. What percent of variation in systolic
blood pressure can be explained by the
least squares line?
e. What is the residual value for a diastolic
blood pressure of 90?
8. In a survey of high school students, 25 said
that they have cheated on a test and 14 said
they have not cheated. What is the
probability that a student chosen at random
has cheated?
Construct a frequency distribution for
the data. Use six classes.
b. Construct a histogram.
9. What is the probability of drawing a king or a
diamond from a deck of cards?
10. What is the probability of drawing a king and
then another king on the second draw if there
is no replacement?
11. A question has 4 multiple choice answers.
a.
Find the probability of guessing an
incorrect answer.
b. If there are 5 questions, what's the
probability of getting all 5 correct?
16. If 80% of the applicants are able to pass a
driver's proficiency road test, find the
mean, variance, and standard deviation of the
number of people who pass the test in a
sample of 300 applicants.
17. The mean score on a standardized test is
120 with a standard deviation of 14.
a.
12. The probability of being a college graduate is
18%. If 5 people are asked if they
graduated from college, what is the
probability that 3 people were asked before
a college graduate was found?
13. The results of a survey are shown below.
18.
Male
Female
Yes
135
105
No
39
87
Maybe
4
12
a.
Find the probability of selecting a
male.
b. Find the probability of a yes or a
maybe.
c. Find the probability of a female and a
yes.
d. Find the probability of being a male,
given that the answer was no.
e. Find the probability of a no or
female.
14. Given the following probability distribution,
find the following.
x
p(x)
1
0.08
2
0.13
3
0.18
4
0.22
5
0.33
a. mean
b. standard deviation
c. P( x  3)
d. Probability that x is within 1
standard deviation of the mean.
15. If 60% of all women are employed outside
the home, find the probability that in a
sample of 20 women,
a. Exactly 15 are employed.
b. At least 10 are employed.
6
0.06
What is the probability of a student
scoring at most a 103?
b. What is the probability of a student
making between a 110 and 125?
c. What is the cutoff score for the top
10% of the grades?
d. If a sample of 100 scores are
analyzed, what’s the probability that
the sample mean is at least 121?
Just before a referendum on a school
budget, a local newspaper polls 400
voters in an attempt to predict whether
the budget will pass. Suppose that the
budget actually has the support of 52%
of the voters. What's the probability
the newspaper's sample will be less than
50%?
19. A bottling machine is operating with a
standard deviation of 0.12 ounces. Suppose
that in a SRS of 36 bottles, the machine
inserted an average of 16.1 ounces into each
bottle. Find & interpret a 90% confidence
interval for the mean amount in each bottle.
20. Ball bearings are manufactured by a process
that results in a standard deviation in
diameter of 0.025 inch. What sample size
should be chosen if we wish to be 99% sure
of knowing the diameter to within 0.01 inche?
21. In a SRS of machine parts, 18 out of 225
were found to have been damaged in
shipment. Find a 95% confidence interval
for the proportion of machine parts that are
damaged in shipment.
22. How many executives should be interviewed
if an estimate is desired at the 99%
confidence level to be within 0.06 of the
true proportion of executives who believe
their workers need more vacation time?