Statistics and Data Analysis: A Comprehensive Guide with Solved Examples
1) A manufacturer claims that only 5% of the products it manufactures have some sort of defect. The
preceding sentence describes a (a):
A) Variable B) Deleted C) Parameter
D) Statistical
2) In a random sample of 500 students found that 45% of them buy their books
text. The above statement describes a (a):
A) Statistical
B) Benchmark C) Variable D) Deleted
3) The distance traveled by a car before you stop once the brakes are applied is an example
of a variable:
A) Quantitative continuous
B) Qualitative C) Quantitative discrete
4) The weight of a canned product is an example of a variable:
A) Quantitative discrete B) Qualitative C) Quantitative continuous
5) A market researcher wants to determine the percentage of citizens in this new year
plan to go on vacation. The type of study that describes this statement is:
A) Observational Retrospective B) cross-sectional
C) Experimental D) Prospective Observational
6) A sociologist wants to determine the percentage of citizens who went to vote in elections
for governor were held last year in a state. The type of study that describes
this statement is:
A) Observational Retrospective
B) cross-sectional
C) Experimental D) Prospective Observational
7) A sociologist has varied as desired to determine the annual rate of divorces in a given city. The
plans to analyze the records from 1950 to date in regard to the divorce rate. The type of
study describing this statement is:
A) Experimental B) Retrospective Observational
C) cross-sectional D) Prospective Observational
8) A taxi company wants to determine which of the two tire types A and B has a higher
performance. To achieve this, has decided to put a tire of each type at random in the back
each of the 10 taxis that were used for this purpose. Then the cars will be subject to a number of
tests in different driving conditions to determine the wear on each tire’s type
type of study described in this statement is:
A) Observational Prospective B) Retrospective Observational
C) cross-sectional D) Experimental
9) A researcher conducts a poll about toughening the penalties for driving
fortified. He decides to pollsters at different points of greater affluence and
interviewing adults who pass through there during the days he has decided to visit those
places. The above statement is describing sampling
A) Laminated
B) Cluster
C) Convenience
D) Systematic
E) Simple Random
10) The president of the association of foreign students conducted a survey to identify
what are the most common problems for students coming from outside to
integrated into college life. The school records department has provided a
list of foreign students has prepared ballots in an amount equal to the number of
students from the list and placed in a box to take a random number of ballots for
select students to be interviewed. The above statement is describing a
> Sampling
A) Cluster
B) Systematic
C) Stratified
D) Simple Random
E) Convenience
11) A nursery has gathered for a group of houses in a certain sector of the city, the surface in
square meters of front gardens that use some type of grass.
Dimensions
(in m2) No. Of Dwellings
0 to 14 2
15 to 19 12
20 to 24 20
25 to 29 21
30 to 34 13
35 to 39 2
What percentage of the homes tested have a garden with an area of at least 25
square meters?
A) 36.00% B) 34.00% C) 48.57% D) 51.43%
12) The data below represent the waiting times in minutes to be served in a
customer service office a shop were a group of clients seen
at random.
What percent of customers had a waiting time between 2.5 and 11.5 minutes?
A) 67.5%
B) 6.75% C) 32.5% D) 65.0%
13) The sales, in thousands of dollars, made by a group of vendors last month
were summarized in the following descriptive measures.
Which of the following values would be more appropriate as a measure of center to analyze the
data?
A) 2,565
B) 8.22 C) 5.6094 D) 13.07
14) There have been the time required to service car in two restaurants
fast food and have been summarized in the following descriptive measures.
Restaurant A Restaurant B
Average 186.3 262.5
Median 184 262.5
Standard Deviation 63.9 129.0
Variance 4081.7 16644.3
Range 195 407
Minimum 92 74
Maximum 287 481
n 60 60
Which of the following restaurants have greater consistency in the time to give
Car service?
A) Restaurant A
B) Both have the same consistency in the service times
C) Restaurant B
D) can not be determined with this information
15) The sales, in thousands of dollars, made by a group of vendors last month
were summarized in the following descriptive measures.
According to the results of the table, what would the shape of the distribution of values
Sales of these workers?
A) Symmetrical
B) skewed left
C) right skewed
D) Can not determine from the information in Table
16) Tests to determine the mileage per liter of three different cars. The
Results are presented with the following box plots (boxplot):
Which of the following statements are correct regarding the values of mileage per gallon?
I. All three cars have the same interquartile range.
II. The car B has an approximately symmetrical distribution.
III. The car B has a smaller range.
A) I and II B) II and III C) I and III D) Only IE) Only II
17) Which of the following expressions involving probability values is true?
I. P (A) = 2 / 3, P (A) = 1 / 3
II. P (B) = 12.0%
III. P (C) = -1.5%
A) I and II B) I only
C) II and III D) Only II E) Only III
18) According to the rule of infrequent occurrence, Which of the following values of probability
associate to a rare or unusual event?
I. P (A) = 0,018
II. P (A) = 0.0078
III. P (A) = 0,078
A) Only I> B) I and II
C) III only D) I, II and III E) Solo II
19) It is known that the monthly income of workers in a given locality have a distribution
normal average of $ 3500 and a standard deviation of $ 300. If a researcher has chosen a
random sample of 25 employees and want to determine the probability of observing a
top half of a $ 4000. To find this value, which one of the situations is the
researcher?
A) You can use the normal distribution because the population standard deviation known
B) No normal distribution they valid because although transfer times are
normally distributed, the sample is less than 30
C) they valid normal distribution because the population standard deviation known and
population has a bell-shaped distribution
D) Do not they valid normal distribution because transport times are distributed
bell shape.
E) they valid normal distribution because the sample is less than 30 and known s.
20) A researcher wants to estimate for a particular school district, the average time per week you
spend watching television for children in 6th grade. She took a random sample of 25
students and asked them for the hours they devote to watching television. He found that the
average this group of students was 10.5 hours per week. She knows, from previous studies,
that the population standard deviation is 4.0 hours and that the distribution under these conditions
is skewed to the left. To obtain a confidence interval of 99% on average to
week you spend watching television the 6th grade students of that district, she should
use
A) The t distribution
B) Neither the distribution nor the t distribution Z Must seek other methods of estimation
C) The distribution Z
D) can not be determined due to lack of information
21) The manager of the college bookstore wants to estimate the percentage of students
purchase textbooks for the class of statistics.
He has taken a random sample of 600
students and asked them if they purchased this textbook for the class of statistics. Del
total respondents found that 320 of them bought the textbook for that class.
To obtain a confidence interval 90% to the actual proportion of students, he should
use
A) Neither the distribution nor the t distribution Z Must seek other methods of estimation.
B) The distribution Z
C) The t distribution
D) Can not determine which distribution to use for lack of information
22) The manager of the college bookstore wants to estimate the percentage of students
purchase textbooks for the class of statistics. He has taken a random sample of 600
students and asked them if they purchased this textbook for the class of statistics. Del
total respondents found that 320 of them bought the textbook for that class.
A confidence level of 95% obtained a range for the actual proportion of students
goes from 0493 to 0573. What would be the most appropriate interpretation for this result?
A) We can say with 95% certainty that the actual percentage of students who
purchase textbooks for the class of statistics is contained in the range extending from
49.3% to 57.3%
B) There is a 95% confidence that the sample percentage of students who acquire
> textbooks for the class of statistics is between 49.3% and 57.3%
C) The probability that the actual percentage of students who purchase textbooks
for the kind of statistic has a value between 49.3% and 57.3% is 0.95
D) 95% of the samples of 600 students have taken a percentage of sample
between 49.3% and 57.3%
23) has been selected a random sample of 150 students and asked how long it
engaged to perform weekly tasks in a mathematics course. There were a range of
98% confidence for the population mean. The range is from 5.2 to 8.3 hours. What would be the
more appropriate interpretation of this result?
A) It has a 98% certainty that the average time they devote to the tasks
student population of math class is contained in the interval between
from 5.2 to 8.3 hours a week.
B) There is a 98% chance that the average time they devote to the tasks
student population of the mathematics course is a value between 5.2 and 8.5 hours to
week.
C) 98% of the samples of size 150 will sample in half the time devoted to
the completion of tasks in math class that is in the range of 5.2 to 8.5
hours a week.
D) It is estimated that 98% of all students in math class they spend from 5.2
and 9.3 Hotas a week.
24) The Carter Motor Company says its new sedan, Libra, but has an average output
Beyond 23 miles per gallon in the city. Which of the following options are represented
null and alternative hypotheses to test the claim of this company?.
A) H0: ì> 23
H1: ì = 23
B) H0: ì <23
H1: ì = 23
C) H0: ì = 23
H1: ì> 23
D) H0: ì = 23
H1: ì <23
25) In an article in a sociology journal states that at least 66% of parents
Americans share with their wives the responsibility to monitor homework
of their children. In a city in the state of California has conducted a study involving
A random sample of 234 parents and found that 138 parents said sharing
responsibility with their wives to monitor their children’s homework. At a level of
the 0.05 significance test was performed by STATDISK and obtained the following
Results:
Which of the following pairs of hypotheses can prove the assertion of the article?
A) Ho: p> 0.66
H1: p <0.66
B) Ho: p = 0.66
H1: p> 0.66
C) Ho: p <0.66
H1: p> 0.66
D) Ho: p = 0.66
H1: p <0.66
26) In an article in a sociology journal states that at least 66% of parents
Americans share with their wives the responsibility to monitor homework
of their children. In a city in the state of California has conducted a study involving
A random sample of 234 parents and found that 138 parents said sharing
responsibility with their wives to monitor their children’s homework. At a level of
> 0.05 significance test was performed by STATDISK and obtained the following
Results:
Which of the following options represent the final conclusion?
A) The sample does not provide significant evidence to conclude that the assertion of the article is
false. Therefore, it is not excluded that at least 66% of American parents
share with their wives the responsibility to supervise their children’s homework.
B) The sample does not provide significant evidence to conclude that the assertion of the article is
true. Therefore, one can say that no more than 66% of parents
Americans share with their wives the responsibility to supervise the work
their children’s school.
C) The sample provides significant evidence to conclude that the assertion of the article is
false. Therefore, one can say that less than 66% of American parents
share with their wives the responsibility to supervise their children’s homework.
D) The sample provides significant evidence to conclude that the assertion of the article is
true. Therefore, one can say that at least 66% of American parents
share with their wives the responsibility to supervise their children’s homework.