AP Stat Final
For a random sample of 20 professional athletes, there is a strong linear relationship between the number of hours that exercise per week and their resting heart rate. For the athletes in the sample, those who exercise more hours per week have a lower resting heart rate than those who exercise less. Which of the following is a reasonable value for the correlation between the number of hours of athletes per week in their arresting heart rate?
-0.87
A summer resort rents row boats to customers but does not allow more than four people to boat. Each boat is designed to hold no more than 800 lb. Suppose the distribution of adult males who weren't boats including their closing gear, is normal with a mean of 100 lb in a standard deviation of 10 lb. If the weights of individual passengers are independent, what's the probability that a group of four adult male passengers will exceed the acceptable weight limit of 800 lbs?
0.023
Add a sporting event, cheerleaders will throw 50 bundle t-shirts into the crowd. The t-shirt sizes consist of 10 small, 15 medium, in the remainder either large or extra large. Suppose Anna catches a t-shirt. What is the probability that she will catch a t-shirt that is not a size small?
0.80
An exponential relationship exists between the explanatory variable and the response variable and a set of data. The common logarithm of each value of the response variable is taken, and the least squares regression line has an equation of log(y) = 7.3 - 1.5x. Which of the following is closest to the predicted value of the response variable for x = 4.8?
1.26
A pharmaceuticalcompany manufacturers medicine to reduce pain caused by migraine headaches. The company is investigating whether a new medicine is more effective in reducing pain than the current medicine. A random sample of 500 participants who experience migrants will selected, and the participants were randomly assigned to one of two groups in equal size. The first group received the current medicine in the second group of the new medicine. When a participant experience a migraine, here she would instruct it to take the medicine and, 15 minutes after taking the medicine, to rate the pain relief on a scale of 1 to 10, with one being not really content being complete relief. At the end of six months, the average pain relief for each participant was calculated. Which of the following is the best description of the study?
An experiment using a completely randomized design
Which of the following statements is true about a distribution that appears to have a gap when displayed as a histogram?
The distribution has a region between two data values where no data was observed
The following histogram shows the ages, in years, of the people who attended a documentary at a movie theater. Based on the histogram, which is the following statements best described their relationship between the mean and the medium of the distribution of ages?
The mean is most likely less than the median because the distribution is skewed to the left
The following bar chart displays the relative frequency of responses of students, by grade level, when asked, do you volunteer in a community service activity? Which of the following statements is not supported by the bar chart?
The number of 10th grade students who responded yes was greater than the number of 9th grade students who responded yes
Under which of the following conditions is it preferable to use stratified random sampling rather than simple random sampling?
The population can be divided into strata so that the individuals in each stratum are as much alike as possible
Nyasha's financial literacy project involved comparing the annual sales of companies in Canada and companies in the United States that produce software. Using the ratio of one Canadian dollar to 0.75 United States dollar, she converted all annual sales from the Canadian company's into United States dollars. For which of the following will the value of the statistic for the annual sales in Canadian dollars be equal to the value of the corresponding statistic in the United States dollar?
The standardized score of the minimum anual sales
The quality control manager of a large factories concerned about the numbers of defective items produced by workers. 30 workers at the factory agreed to participate in a study of three different incentive plans to help reduce the number of defective items produced. These plans will be randomly assigned to the workers so that 10 workers receive each plan. The reduction in the number of defective items produced by each worker will be recorded two weeks after the plans are implemented. Which of the following best describes why a completely randomized designed is an appropriate designed to use in this situation?
There's no blocking variable, and incentive plans will be randomly assigned to workers
In the design of a survey, which of the following best explains how to minimize response bias?
Carefully word and field test survey questions
The residual plots from five differently squares regression lines are shown below. Which of the following plots contains the strongest evidence that it's regression line is an appropriate model for the data and is consistent with the assumptions required for inference for regression?
the one with the most random points
Consider n pairs of numbers (x1,y1), (x2,y2), ... , (xn,yn). The mean and standard deviation of the x values are x = 5 and s = 4 respectively. The mean and the standard deviation of the y values are y = 10 and s = 10 respectively. Of the following which could be the least squares regression line?
y = 8.5+0.3x
Exercise physiologists are investigating the relationship between lean body mass and the resting metabolic rate in sedimentary males. Based on the computer output above, which of the following is the best interpretation of the value of the slope of the regression line?
For each additional kilogram of lean body mass, the resting metabolic rate increases on average but 22.563 calories per day
A local company is interested in supporting environmentally friendly initiative such as carpooling among employees. The company surveyed all of the 200 employees at the downtown offices. Employees responded as to whether or not they own a car into the location of the home where they live. The results are shown in the table will o. Which of the following statements about a randomly chosen person from these 200 employees is true?
If the person ends a car, he or she is more likely to live elsewhere in the city than to live in the downtown area in the city
Mateo plays on his school basketball team. From past history he knows that his probability of making a basket on a free throw is 0.8. Suppose he wants to create a simulation using random numbers to estimate the probability of making at least three baskets on his next five free throw attempts. Which of the following assignments of the digits 0 to 9 could be used for the simulation?
Let the digits from 0 to 7 represent making a basket in the digits 8 and 9 represent not making a basket
The probability that a randomly selected visitor to a certain website will be asked to participate in an online survey is 0.4. Avery claims that for the next five visitors to the site, two will be asked to participate in the survey. Is Avery interpreting the probability correctly?
No because 0.4 represents a probability in the long run over many visitors to the site
For specific species of fish in a pond, a wildlife biologist wants to build a regression equation to predict the weight of a fish based on its length. The biologist collects a random sample of this species of fish and finds that the lengths vary from 0.75 to 1.35 in. The biologist uses the data from the sample to create a single linear regression model. Would it be appropriate to use this model to predict the way of a fish of this species that is 3 in long?
No because 3 in falls above the maximum value of the lengths in the sample
High school science teacher has 78 students. Of those students, 35 are in the band in 32 are on a sports team. They're 16 students who are not in the band or on a sports team. One student from the 78 students will be selected at random. Let event be represent the event of selecting a student in the band, and let event ask represent the event of selecting a student on a sports team. Or beat and ask mutually exclusive events?
No because P(B or S)=5/78
To check the effect of cold temperatures on the elasticity of two brands of rubber bands, one box of brand A and one box of brand B rubber bands are tested. Test bands from the brand A box are placed in a freezer for two hours and 10 bands from the brand B box are kept at room temperature. The amount of stretch before breakage is measured on each rubber band, and the mean for the cold bands is compared to the mean for the others. Is this a good experimental design?
No because temperature is confounded with brand
According to a report for veterinarians in the United States, 36.5% of households in the United States own dogs and 30.4% of households in the United States on cats. If one household in the United States is selected at random, what is the probability of that the selected household will own a dog or a cat?
Not enough information is given to determine the probability
The following list shows the numbers of video games sold at a game store each day for one week. 15, 43, 50, 39, 22, 16, 20 which of the following is the best classification of the data in the list?
Quantitative and discrete
The probability that a new microwave oven will stop working in less than 2 years is 0.05. The probability that a new microwave oven is damaged during delivery and stops working in less than 2 years is 0.04. The probability that a new microwave oven is damaged during delivery is 0.10. Given that a new microwave oven is damaged during delivery what is the probability that it stops working in less than 2 years?
0.40
A restaurant manager collected data to predict monthly sales for the restaurant from monthly advertising expenses. The model created from the data showed that 36% of the variation in monthly sales could be explained by monthly advertising expenses. What was the value of the correlation coefficient?
0.60
A complex electronic device contains three components, a b and c. The probabilities of failure for each component if any one year are 0.01, 0.03, and 0.04. If any one component fails the device will fail. If the components fail independently of when another, what is the probability that the device will not fail in one year?
0.922
One student from the school will be selected at random. What is the probability that the student is in the age group of 6 to 8 years given that the selected student responded joy?
28/89
The weight of adult male grizzly bears living in the wild in the continual United States is approximately normally distributed with a mean of 500 lbs in a standard deviation of 50 lb. The weight of adult female grizzly bears is approximately normal distributed with a mean of 300 lbs in a standard deviation of 40 lb. Approximately what would the weight of a female grizzly bear with the same standardized score as a male grizzly bear with a weight of 530 lb?
324 lb
A researcher studying the effect of genetically modified and non genetically modified corn on the weight gain of lambs. The sex and genetics of the lamps can affect their weight gain. Five sets of male twin lands and five sets of female twin lamps for a total of 20 lamps are available for the study. The lamps will be randomly assigned to a diet of either GM or NGM diet of corn. Wake gain will be recorded for each lamp after about five weeks on the diet. Which of the following designs would be best to use in the study
A matched pairs design. For each set of twins, randomly assigned one twin to the GM diet in the other twin to the NGM diet
Which of the following is the best description of a positive association between two variables?
As the value of one of the variables increases, the value of the other variable tends to increase
In a certain school district, students from grade 6 through grade 12 can participate in a school sponsored community service activity. The following bar chart shows the relative frequencies of the students from each grade who participate in the community service activity. Which of the following statements is supported by the bar chart?
Grade 12 had the least relative frequency of the participating students
The student government at a high school wants to conduct a survey of student opinion. It wants to begin with a simple random sample of 60 students. Which of the following survey methods will produce a simple random sample?
Number the students in the official school roster. Use a table of random numbers to choose 60 students from the roster for the survey
The following frequency table shows the responses from a group of college students who are asked to choose their favorite ice cream flavor. Which of the following statements is not supported by the table?
One-half of the students chose vanilla or chocolate
A polling firm is interested in surveying a representative of sample registered voters in the United States. The firm has automated its sampling so that the random phone numbers within the United States are called. Each time a number is called the procedure below is followed. Some people claim that the procedure being used is not permit the results to be extended to all registered voters. Which of the following is not a legitimate concern about the procedure being used?
Registered voters with unlisted telephone numbers maybe underrepresented in the sample
The table shows data that were collected from people who attended a certain high school basketball game and indicates the team each person rooted for and whether each of these people purchased food during the game. A person who attended the game will be selected at random. Which of the following correctly interprets mutually exclusive events represented by the table?
Rooting for the home team in rooting for the way team
The following dot bot shows the scores of 25 people who played an online trivia game. Which of the following statements is the best description of the distribution of scores?
The distribution is skewed right
One way to measure the duration of subterranean disturbances such as earthquakes and mining is to calculate the root mean square time. The following histogram summarize the distributions of the root mean square times for two sources of disturbances. Based on the histograms which of the following correctly compares to two distributions?
The median of the earthquake disturbances is less than the median of the mining disturbances
As a part of a study on facility needs, the administrators of a university wanted to estimate the percent of students who use the exercise facilities on a regular basis. From the 34,000 students who attend the University, a random sample of 370 male students and 400 female students with selected. Of the 770 students selected, 493 students indicated that they used the exercise facilities on a regular basis. What are the population and sample of the study?
The population is the 34,000 students who attend the University, in the sample is the 770 student who were selected
A non-profit organization plans to hold a raffle to raise funds for its operations. A total of 1,000 raffle tickets will be sold for $1 each. After all the tickets are sold, one ticket will be selected at random and its owner will receive $50. The expected value for the net game for each ticket is -$0.95 . What is the meaning of the expected value in this context?
The ticket owners lose an average of $0.95 per raffle ticket
Researchers conducted a study to investigate the effects of self-drink consumption on fat stored in muscle tissue. From a sample of 80 adult volunteers, 40 were randomly assigned to consume 1 liter of a soft drink each day. The remaining 40 were asked to drink one liter of water each day and not consume any softer drinks. At the end of six months, the amount of fat stored in each person's muscle tissue was recorded. The people in the group who drank the soft drink had on average a higher percentage of fat stored in the tissue than the people who drink only water. Which of the following is the most appropriate conclusion?
There's evidence that consuming soft drinks causes more fat storage in muscle tissues than drinking only water, and they conclusion can be generalized to adults similar to those in the study
Which of the following questions about cars in a school parking lot will allow for the collection of a set of categorical data?
What are the colors of the cars in the lot?
For a role of a fair die, each of the outcomes 1 2 3 4 5 and 6 is equally likely. A red dye and a green dye are rolled simultaneously, in the difference of the outcomes is computed. This is repeated for a total of 500 rolls of the pair of dice. Which of the following graphs best represents the most reasonable distribution of the differences?
c
