MATH 1280: Introduction to Statistics/ Qs with
Certified Ans/ 2024-2025
The location of the highest bar of the bar plot for the month of September represents the fact
that? - Answer: D) 10 incoming calls came during 6 days of the month of September.
The highest bar of the bar plot for the month of September is placed over the value "10" and its
height is 6 units.
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)
Frequency of Hurricane Direct HitsCategory# Direct HitsRelative Freq.Cum. Relative Freq.1
0.39930 0.3993272 3 0.2601 4 0.0659 5 0.01101.0000 - Answer: What is the relative frequency
of direct hits that were category 2 hurricanes?
Page 1 of 10
, A) 0.2637
The total of all relative frequencies is 1.000. Denote by p the relative frequency of category 2
hurricanes. Observe that0.3993 + p + 0.2601 + 0.0659 + 0.0110 = 1.0000Consequently,p = 1 -
0.3993 + 0.2601 + 0.0659 + 0.0110 = 1 - 0.7363 = 0.2637
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 questions: (The numerical answer that
you provide should be of the form "0. XXXX", with 4 digits to the right of the zero.) - Answer:
The relative frequency that flossed 6 times per week is:
Answer: 0.05
It is given that the total number of adults with gum disease is 60. There are 3 such adults that
flossed 6 times per week. Therefore, the relative frequency is 3/60 = 0.0500
The relative frequency that flossed at least once a week is: - Answer: Answer: 0.55
The relative frequency of adults that do not floss at all is 0.4500. All other adults floss at least
once a week. Their relative frequency is 1.0000 - 0.4500 = 0.5500.
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: C) 72
Page 2 of 10
Certified Ans/ 2024-2025
The location of the highest bar of the bar plot for the month of September represents the fact
that? - Answer: D) 10 incoming calls came during 6 days of the month of September.
The highest bar of the bar plot for the month of September is placed over the value "10" and its
height is 6 units.
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)
Frequency of Hurricane Direct HitsCategory# Direct HitsRelative Freq.Cum. Relative Freq.1
0.39930 0.3993272 3 0.2601 4 0.0659 5 0.01101.0000 - Answer: What is the relative frequency
of direct hits that were category 2 hurricanes?
Page 1 of 10
, A) 0.2637
The total of all relative frequencies is 1.000. Denote by p the relative frequency of category 2
hurricanes. Observe that0.3993 + p + 0.2601 + 0.0659 + 0.0110 = 1.0000Consequently,p = 1 -
0.3993 + 0.2601 + 0.0659 + 0.0110 = 1 - 0.7363 = 0.2637
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 questions: (The numerical answer that
you provide should be of the form "0. XXXX", with 4 digits to the right of the zero.) - Answer:
The relative frequency that flossed 6 times per week is:
Answer: 0.05
It is given that the total number of adults with gum disease is 60. There are 3 such adults that
flossed 6 times per week. Therefore, the relative frequency is 3/60 = 0.0500
The relative frequency that flossed at least once a week is: - Answer: Answer: 0.55
The relative frequency of adults that do not floss at all is 0.4500. All other adults floss at least
once a week. Their relative frequency is 1.0000 - 0.4500 = 0.5500.
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: C) 72
Page 2 of 10
