## MATH 399N Week 3 MyStatLab Quiz (3 Versions)

##### MATH 399N Week 3 MyStatLab Quiz

Solutions (Version 1)

1. **Question: 1.1.41 **Determine whether the given value is a statistic or a parameter.

In a study of all 1876 professors at a college, it is found that 40% own a television.

**2. Question: 1.2.6 **Determine whether the following statement is true or false. If it is false, rewrite it as a true statement.

Data at the ratio level cannot be put in order.

**3. Question: 1.2.33 **What is an inherent zero? Describe three examples of data sets that have inherent zeros and three that do not.

**4. Question: 1.3.25 **Identify the sampling techniques used, and discuss potential sources of bias (if any). Explain. Assume athe population of interest is the student body at a university. Questioning students as they leave a university parking lot, a researcher asks 385 students about their dating habits.

**5. Question: 2.2.7 **Match the plot with a possible description of the sample.

**6. Question: 2.2.17 **Use a stem-and-leaf plot to display the data. The data represent the heights of eruptions by a geyser. What can you conclude about the data?

101 90 110 150

140 120 100 130

110 108 118 100

96 107 109 120

110 130 97 121

**7. Question: 2.4.15 **The ages (in years) of a random sample of shoppers at a gaming store are shown. Determine the range, mean, variance and standard deviation of the sample data set.

12, 17, 23, 13, 16, 17, 19, 16, 15, 15

**8. Question: **The mean value of land and buildings per acre from a sample of farms is $1400, with a standard deviation of $100. The data set has a bell-shaped distribution. Using the empirical rule, determine which of the following farms, whose land and building values per acre are given, are unusual (more than two standard deviations from the mean). Are any of the data values very unusual (more than three standard deviations from the mean)?

$1410 $1646 $1275 $1000 $1449 $1275

**9. Question: 9.1.15 **Suppose the scatter plot shows the results of a survey of 30 randomly selected males ages 24 to 35. Using age as the explanatory variable, choose the appropriate description for the graph. Explain your reasoning.

- Age and body temperature
- … balance on student loans
- Age and income
- Age and height

**10. Question: 9.2.11 **Match the description below its symbol(s).

The mean of the y-values

**11. Question: **Find the equation of the regression line for the given data. Then construct a scatter plot of the data and draw the regression line. (The pair of variables have significant correlation.) Then use the regression equation to predict the value of y for each of the given x-values, if meaningful. The table below shows the heights (in feet) and the number of stories of six notable buildings in a city.

**12. Question: 9.3.9 **Use the value of the linear correlation coefficient to calculate the coefficient of determination. What does this tell you about the explained variation of the data about the regression line? About the unexplained variation?

r = 0.264

**13. Question: 9.4.1 **The equation used to predict college GPA (range 0-4.0) is ŷ = 0.21 + 0.52x_{1} + 0,002x_{2}, where x_{1} is high school GPA (range 0-4.0) and x_{2} is college board score (range 200-800). Use the multiple regression equation to predict college GPA for a high school GPA of 3.4 and a college board score of 500.

##### MATH 399N Week 3 MyStatLab Quiz

Solutions (Version 2)

**1. Question: 2.4.13 **The number of regular season wins for 10 football teams in a given season are … below. Determine the range, mean, variance, and standard deviation of the population data set.

2, 10, 15, 5, 14, 9, 12, 10, 2, 9

**2. Question: 2.3.15 **Consider a frequency distribution of scores on a 50-point test where a few students scored much lower than the majority of students. Match this distribution with one of the graphs shown below.

**3. Question: 9.1.15 **Suppose the scatter plot shows the results of a survey of 37 randomly selected males ages 24 to 35. Using age as the explanatory variables, choose the appropriate description for the graph. Explain your reasoning.

**4. Question: 9.2.17-T **Find the equation of the regression line for the given data. Then construct a scatter plot of the data and draw the regression line. (The pair of variables have a significant correlation). Then use the regression equation to predict the value of y for each of the given x-values, if meaningful. The table below shows the heights (in feet) and the number of stories of six notable buildings in a city.

Height, x | 758 | 621 | 518 | 510 | 492 | 483 |

Stories, y | 51 | 47 | 52 | 25 | 39 | 32 |

**5. Question: 9.4.3 **The equation used to predict the total body weight (in pounds) of a female athlete at a certain school is = – 124 + 3.42x_{1} + 1.74x_{2}, where x_{1} is the female athlete’s height (in inches) and x_{2} is the female athlete’s percent body fat, measured as x_{2}%. Use the multiple regression equation to predict the total body weight for a female athlete who is 64 inches tall and has 26 % body fat.

**6. Question: 1.1.41 **Determine whether the … value is a statistic or a parameter.

A sample of students is selected and it is found that 45% own a television.

**7. Question: 1.3.25 **Identify the sampling techniques used, and discuss potential sources of bias (if any). Explain. Assume the population of interest is the student body at a university. Questioning students as they leave a university library, a researcher asks 338 students about their eating habits.

**8. Question: 2.2.5 **Match the plot with a possible description of the sample.

**9. Question: 9.3.7 **Use the value of the linear correlation coefficient to calculate the coefficient of determination. What does this tell you about the explained variation of the data about the regression line? About the unexplained variation?

r = – 0.996

**10. Question: 1.2.33 **What is an inherent zero? Describe three examples of data sets that have inherent zeros and three that do not. Choose the correct answer below.

**11. Question: **Match the description below with its symbol(s).

The mean of the y-values. Select the correct choice below.

## STATUS

**12. Question: 2.4.33 **The mean value of land and buildings per acre from a sample of farms is $1200. The data set has a bell-shaped distribution. Using the empirical rule, determine which of the following farms, whose land and building values per acre are …, are unusual (more than two standard deviations from the mean). Are any of the data values very unusual (more than three standard deviations from the mean)?

$1204 $1405 $1327 $885 $1340 $1045

**13. Question: 2.2.18 **Use a stem-end-leaf plot to display the data. The data represents the amount of hours employees at a certain company spend driving to and from work for a given month. What can you conclude about the data?

39 54 35 48

38 40 36 50

47 53 43 56

29 23 60 39

60 41 34 36

**14. Question: 1.2.4 **Determine whether the following statement is true or false. If it is false, rewrite it as a true statement.

For data at the interval level, you cannot calculate meaningful differences between data entries. Choose the correct answer below.

##### MATH 399N Week 3 MyStatLab Quiz

Solutions (Version 3)

**Question:**Identify the sampling techniques used, and discuss potential sources of bias (if any). Explain**Question:**Match the description below with its symbol(s).**Question:**Use a stem-and-leaf plot to display the data. The data represent the heights of eruptions by a geyser. What can you conclude about the data?**Question:**Suppose the scatter plot shows the results of a survey of 48 randomly selected males ages 24 to 35. Using age as the explanatory variable, choose the appropriate description for the graph. Explain your reasoning.**Question:**Determine whether the approximate shape of the distribution in the histogram is symmetric, uniform, skewed left, skewed right, or none of these.**Question:**Determine whether the following statement is true or false. If it is false, rewrite it as a true statement. Data at the ratio level cannot be put in order.**Question:**The ages (in years) of a random sample of shoppers at a gaming store are shown. Determine the range, mean, variance, and standard deviation of the sample data set.**Question:**Height of men on a baseball team have a bell-shaped distribution with a mean of 179 cm and a standard deviation of 8 cm. using the empirical rule, what is the approximate percentage of the men between the following values?- 171 cm and 187 cm
- 155 cm and 203 cm

**Question:**Determine whether underlined numerical value is a parameter or a statistic. Explain your reasoning. A survey of 42 out of hundreds in a dining hall showed that__17__enjoyed their meal.**Question:**Use the value of the linear correlation coefficient to calculate the coefficient of determination. What does this tell you about the explained variation of the data about the regression line? About the unexplained variation?**Question:**Find the equation of the regression line for the given data. Then construct a scatter plot of the data and draw the regression line. (The pair of variables have a significant correlation.) then use the regression equation to predict the value of y for each of the given x-values, if meaningful. The number of hours 6 students spent for a test and their scores on that test are shown below.**Question:**The region of a country with a longest life expectancy for the past six years is shown below.

Southern Northwest Eastern Western Southwest Southeast

Determine whether the data are qualitative or quantitative and identify the data set’s level of measurement.

**13. Question: **The equation used to predict the total body weight (in pounds) of a female athlete at a certain school is = – 127 + 3.64x_{1} + 2.28x_{2}, where x_{1 }is the female athlete’s height (in inches) and x_{2} is the female athlete’s percent body fat, measured as x_{2}%. Use the multiple regression equation to predict the total body weight of female athlete who is 61 inches tall and has 22% body fat.

**14. Question:** Match the plot woth a possible description of the sample……choose the correct answer below