Math 0242 Quiz 3.docx - Math 1342 Quiz 3 Spring 2020 This...

Math 1342
Quiz 3
Spring 2020
This quiz is open notes, but remember that it is helping you prepare for your Math 1342 final.
Submit your answers through BB (either a photo, scanned image, or answers typed into the text
box will work) by the deadline on Monday 4 May 2020.
1. You are told “The average price of a car at the new car dealership in town is $34,100.” Is
this reporting a population parameter or a sample statistic? Explain.
2. You see the results of a survey indicating the types of cars driven by all of the coaches in
the NFL. Is this a population parameter or a sample statistic? Explain.
3. You are conducting a survey about student study habits.
a. What is one categorical (qualitative) variable you might collect data about?
b. What is one quantitative variable you might collect data about?
4. You are given the following information about a data set:
From Excel the mean is 30.94 and the standard deviation is 23.12.
The five number summary is:
Min=0
Q1=15
Median=23
Q3=47.5
Max = 88
a. Between what two values does the middle 50% of the data fall?
b. The mean is 30.94 and the median is 23. What does that mean about whether or not
there are outliers in the data set? Explain.
c. Draw a box and whisker plot for the data using the information you are given.
d. Use the empirical rule to determine between which two numbers do you expect to
find the middle 95% of the data?
5. Give an example of a data set containing 5 numbers which has a standard deviation of
zero.
6. Explain when to use the median instead of the mean for a measure of center for a data
set.

7. Explain the difference between univariate and bivariate data.
8. Give an example of univariate data.
9. In what range is the value of r when bivariate data exhibits a positive relationship?
10. Use this scatterplot to answer each of the questions below:
a. Is there a linear relationship between the variables? Briefly explain.
b. Is the relationship positive or negative? Explain.
c. When you find the least-squared regression line for this bivariate data, will the
slope of the line be positive or negative? Explain.
11. Suppose the following estimated regression equation was determined to predict salary
based on years of experience:
Estimated salary=25,689.10+2148.35 (Years of Experience)
a. What is the independent variable?