Certified Solutions.
The population in this survey is: - Answer: The target of the survey is to assess the service that
costumers get at the dealerships.
The correct answer is: 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.
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,The set of all scores on the standardized test across the country is - Answer: the population
When all the scores for the two classrooms are added and divided by the number of
observations, the resulting value is a - Answer: a statistic
What is the mean score in Group A? - Answer: 8.0625
Load data for Group B into an R object called B, then run this command barplot(table(B)) What
does the bar on the right represent? - Answer: Three students received a score of 10 on the
quiz.
Eighty adults with gum disease were asked the number of times per day they flossed. The
(incomplete) results are shown below. Fill in the blanks in the table and answer the next two
question. - Answer:
The count of people who flossed three times per day is - Answer: 9
The cumulative relative frequency of those who flossed 0 to 2 times per day is - Answer: .6750
Use this information for the next six questions category <- c('a', 'g', 'd', 'a', 'd', 'g', 'g', 'd') speed
<- c(60, 83.3, 71, 64.4, 75, 90, 87, 73) - Answer:
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, The data type of the category object is - Answer: factor
The data type of the speed object is - Answer: numeric
What is the mean of the category object? - Answer: numeric
What is the mean of the category object? - Answer: none of the above
What is the mean of speed (rounded to 1 decimal place)? - Answer: 75.5
What is the sample standard deviation of the speed data (rounded to 1 decimal place)? -
Answer: 10.6
What is the minimum value of the speed data - Answer: 60.0
Some researchers collected data on the number of pairs of shoes that students own. Five
students owned seven pairs, two students owned no pairs, and various students owned
between one and five pairs of shoes. See the data in the frequency table. - Answer:
What is the mean of the number of pairs of shoes that the students owned? - Answer: 3.0
In Chapter 3 the data frame "ex.2", which contained information associated to the blood
pressure of a sample of 150 men and women, was introduced. Let us assume that this sample
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