Page 1 of 24
MATH 1280 INTRODUCTION TO STATISTICS EXAM QUESTIONS AND
CORRECT DETAILED ANSWERS (GRADED A+) LATEST EDITION
Terms in this set (182) Q & A
The population in this survey is:
- answer- The target of the survey is to assess the service that costumers get at the
dealerships. Customers that arrive at dealerships of the company.
The sample in this survey is:
- answer- that arrive at the selected dealerships during the day of visit.
A parameter that may be targeted by this survey is:
- answer- The percentage of costumers that possess a car made by the company.
A statistic that may be used to summarize the outcome of the survey is:
- answer- The percentage, among costumers that were interviewed, of those that do not
possess a car made by the company
The data used to produce the tables and plots is:
- answer- A sample.
The average number of calls that arrived between 8:00 AM and 8:10 AM during the working
days of any month is:
- answer- A parameter.
The average number of calls recorded in the object "Feb" is 5.85. The average in the object
"Sep" is 8.5. The difference between these two numbers is:
- answer- A statistic.
, Page 2 of 24
In which of the months the number of incoming calls between 8:00 AM and 8:10 AM tends to
be smaller?
- answer- February.
The height of the fourth bar from the left of the bar plot for the month of February represents
the fact that?
- answer- In 4 of the days of the month of February there were 5 incoming calls.
The location of the highest bar of the bar plot for the month of September represents the fact
that?
- answer- 10 incoming calls came during 6 days of the month of September.
The next two questions refer to the following relative frequency table on hurricanes that have
made direct hits on the U.S. between 1851 and 2004. Hurricanes are given a strength category
rating based on the minimum wind speed generated by the storm.
(http://www.nhc.noaa.gov/gifs/table5.gif ) (ALTERNATE DOWNLOAD LINK)
- answer-
What is the relative frequency of direct hits that were category 2 hurricanes?
- answer- 0.2637
The relative frequency of direct hits that were AT LEAST a category 3 storm is
- answer- 0.337
Sixty adults with gum disease were asked the number of times per week they used to floss
before their diagnoses. The (incomplete) results are shown below:
Flossing Frequency for Adults with Gum Disease# per WeekFreq.Relative Freq.Cum. Relative
Freq.0270.4500 118 3 0.933363 710.0167
Fill in the blanks in the table and answer the next two question: (The numerical answer that
you provide should be of the form "0.xxxx", with 4 digits to the right of the zero.)
- answer-
, Page 3 of 24
The relative frequency that flossed 6 times per week is:
- answer- 0.05
The relative frequency that flossed at least once a week is:
- answer- 0.55
The number of malfunctioning products per production series was recorded for several
production series. The data was entered into an R object by the name "malfunction". The
next 3 questions refer to the following R code:
- answer-
The sample size is:
- answer- 72
The frequency of production series where there are 4 malfunctioning products is:
- answer- 16
The frequency of production series where there are less than 7 malfunctioning products is:
- answer- 70
The file "ex2.csv" contains information on the blood pressure of a group of healthy
individuals. The file is located in http://pluto.huji.ac.il/~msby/StatThink/Datasets/ex2.csv.
(ALTERNATE DOWNLOAD LINK) Read the data into R and answer the following 4 questions
- answer-
The number of variables is:
- answer- 7
MATH 1280 INTRODUCTION TO STATISTICS EXAM QUESTIONS AND
CORRECT DETAILED ANSWERS (GRADED A+) LATEST EDITION
Terms in this set (182) Q & A
The population in this survey is:
- answer- The target of the survey is to assess the service that costumers get at the
dealerships. Customers that arrive at dealerships of the company.
The sample in this survey is:
- answer- that arrive at the selected dealerships during the day of visit.
A parameter that may be targeted by this survey is:
- answer- The percentage of costumers that possess a car made by the company.
A statistic that may be used to summarize the outcome of the survey is:
- answer- The percentage, among costumers that were interviewed, of those that do not
possess a car made by the company
The data used to produce the tables and plots is:
- answer- A sample.
The average number of calls that arrived between 8:00 AM and 8:10 AM during the working
days of any month is:
- answer- A parameter.
The average number of calls recorded in the object "Feb" is 5.85. The average in the object
"Sep" is 8.5. The difference between these two numbers is:
- answer- A statistic.
, Page 2 of 24
In which of the months the number of incoming calls between 8:00 AM and 8:10 AM tends to
be smaller?
- answer- February.
The height of the fourth bar from the left of the bar plot for the month of February represents
the fact that?
- answer- In 4 of the days of the month of February there were 5 incoming calls.
The location of the highest bar of the bar plot for the month of September represents the fact
that?
- answer- 10 incoming calls came during 6 days of the month of September.
The next two questions refer to the following relative frequency table on hurricanes that have
made direct hits on the U.S. between 1851 and 2004. Hurricanes are given a strength category
rating based on the minimum wind speed generated by the storm.
(http://www.nhc.noaa.gov/gifs/table5.gif ) (ALTERNATE DOWNLOAD LINK)
- answer-
What is the relative frequency of direct hits that were category 2 hurricanes?
- answer- 0.2637
The relative frequency of direct hits that were AT LEAST a category 3 storm is
- answer- 0.337
Sixty adults with gum disease were asked the number of times per week they used to floss
before their diagnoses. The (incomplete) results are shown below:
Flossing Frequency for Adults with Gum Disease# per WeekFreq.Relative Freq.Cum. Relative
Freq.0270.4500 118 3 0.933363 710.0167
Fill in the blanks in the table and answer the next two question: (The numerical answer that
you provide should be of the form "0.xxxx", with 4 digits to the right of the zero.)
- answer-
, Page 3 of 24
The relative frequency that flossed 6 times per week is:
- answer- 0.05
The relative frequency that flossed at least once a week is:
- answer- 0.55
The number of malfunctioning products per production series was recorded for several
production series. The data was entered into an R object by the name "malfunction". The
next 3 questions refer to the following R code:
- answer-
The sample size is:
- answer- 72
The frequency of production series where there are 4 malfunctioning products is:
- answer- 16
The frequency of production series where there are less than 7 malfunctioning products is:
- answer- 70
The file "ex2.csv" contains information on the blood pressure of a group of healthy
individuals. The file is located in http://pluto.huji.ac.il/~msby/StatThink/Datasets/ex2.csv.
(ALTERNATE DOWNLOAD LINK) Read the data into R and answer the following 4 questions
- answer-
The number of variables is:
- answer- 7
