Name: _________________________________________________
Statistics Final Exam Review
Your final exam will be in class on May 23rd and May 24th. You will be completing the Multiple
Choice Section (10 questions) on May 23rd and the open response section (6 questions) on May 24th.
This review sheet is representative of your final exam. You will be given a reference sheet similar to
the one that you were given for the Chapter 7 test.
Directions: For questions #1-10 select the best answer.
1.) Determine whether the given value is a statistic or a parameter:
After inspecting all of 55,000 kg of meat stored at the Wurst Sausage Company, it was
found that 45,000 kg of the meat was spoiled.
(a)
Statistic
(b)
Parameter
(c)
Cannot be determined
2.) Which score has a higher relative position:
Situation 1: a score of 55 on a test for which x  43 and a s 10
Situation 2: a score of 5.0 on a test for which x  4 and s  0.8
Situation 3: a score of 435.6 on a test for which x  396 and s  44
(a)
Situation 1
(b)
Situation 2
(c)
Situation 3
3.) Find the z-score corresponding to the given value and use the z-score to determine whether
the value is unusual. Consider a score to be unusual if its z-score is less than -2.00 or greater
than 2.00.
A body temperature of 99.7F given that human body temperatures have a mean of
98.20F and a standard deviation of 0.62 .
(a)
-2.4
unusual
(b)
2.4
(c)
not unusual
2.4
unusual
(d)
1.5
not unusual
4.) A study conducted at a certain college shows that 54% of the school’s graduates find a job in
their chosen field within a year after graduation. Find the probability that among 9
randomly selected graduates, at least one finds a job in his or her chosen field within a year
of graduating.
(a)
0.540
(b)
0.111
(c)
0.996
(d)
0.999
5.) The following table contains data from a study of two airlines which fly to Small Town, USA.
Number of Flights
which were ON TIME
Number of flights
which were LATE
Podunk Airlines
33
6
Upstate Airlines
43
5
If one of the 87 flights is randomly selected, find the probability that the flight selected
arrived on time given that it was an Upstate Airlines flight.
(a)
11
76
(b)
43
48
(c)
43
87
(d)
5
11
(d)
0.1660
6.) If Z is a standard normal variable, find P(Z  0.97)
(a)
0.8078
(b)
0.8340
(c)
0.8315
7.) Assume that X has a normal distribution with   15.2 and the standard deviation of   0.9 .
Find the probability that X is greater than 16.1.
(a)
0.1550
(b)
0.1587
(c)
0.8413
(d)
0.1357
8.) Find the margin of error for the 95% confidence interval used to estimate the population
proportion when n  186 and x  103.
(a)
0.0643
(b)
0.125
(c)
0.00260
(d)
0.0714
9.) 61 randomly selected light bulbs were tested in a laboratory, 50 lasted more than 500 hours.
Find the point estimate of the true proportion of all light bulbs that last more than 500 hours.
(a)
0.803
(b)
0.450
(c)
0.820
(d)
0.180
10.)
Given that the margin of error is E  $100 and the standard deviation   $403 , find
the minimum sample size required to estimate an unknown population mean  to a 95%
confidence level.
(a)
91
(b)
63
(c)
108
(d)
44
11.)
Identify the sample and the population. Also, determine whether the sample is likely to be
representative of the population.
Situation: 100,000 randomly selected adults were asked whether they drink at least 48 oz of
water each day and only 45% said yes.
Sample:
Population:
Is the sample representative of the population?
12.)
A researcher wants to obtain a sample of 100 school teacers from the 800 school teachers in
the school district. Describe procedures for obtaining a sample of each type:
Random:
Systematic:
Convenience:
Stratified:
Cluster:
13.)
Describe how to find the percentile for a given score in a set of data. How does this relate to
the definition of a percentile score?
14.)
Construct the cumulative frequency and relative frequency distributions that corresponds to
the given frequency distribution.
Days of
Vacation
0-3
16
4-7
20
8-11
14
12-15
24
16-19
26
CUMULATIVE FREQUENCY
Days of
Vacation
Frequency
Cumulative
Frequency
RELATIVE FREQUENCY
Days of
Vacation
Relative
Frequency
15.)
When 343 college students are randomly selected and surveyed, it is found that 110 own a
car. Construct a 99% confidence interval for the true proportion of all college students who
own a car. Then interpret your confidence interval. Make sure you begin by checking that
the necessary requirements are met.
16.)
A group of 52 randomly selected students have a mean score of 20.2 with a standard
deviation of 4.6 on a placement test. Assuming the population standard deviation is equal to
that of our sample, construct a 90 percent confidence interval for the mean score,  , of all
students taking the test. Then interpret your confidence interval. Make sure you begin by
checking that the necessary requirements are met.