Fd of Math I
Name _____________________________________
Week 14 Homework (Due Thursday, December 2)
Use the following chart for #1-4. The following chart gives the average height of girls at certain ages.
After entering the data and following the steps of linear regression on the calculator, this was displayed:
1. Using the information displayed, write the equation of the line of best fit for this data. (Round 2 decimal
places).
2. Determine the correlation coefficient for the equation (round two decimal places). Is this a good fit?
3. Predict the average height of a girl
at 15 years old.
4. Predict the age of a girl whose height
Is approximately 60 inches tall.
5. What does the y-intercept of the linear function represent?
----------------------------------------------------------------------------------------------------------------------------------------------The following chart gives the sales of Hybrid Cars in the United States in various years as well as the
calculator display after data was entered and linear regression steps calculated. (x = 0 represents the year
2001)
6. Write a regression equation. Is this a good fit? Justify your answer.
7. Predict the number of cars sold in 2016.
8. Predict the number of cars sold in 2006. Compare this to the table of values. What is the difference
between the actual and predicted values?
In each situation, tell whether a correlation is likely. If it is, tell whether the correlation reflects a causal
relationship. Explain your reasoning.
9. The number of practice free throws you take and the number of free throws you make in a game.
10. The height of a mountain and the average elevation of the state it is in.
11. The number of hours worked and an employee’s wages.
12. A drop in the price of a barrel of oil and the amount of gasoline sold
13. The number of additional calories consumed and the amount of weight gained.
14. Annual salary and body weight for men.
15. The number of cars traveling over a busy holiday weekend and the number of accidents reported.
16. Which of the following statements shows a relationship that is correlated, but NOT causal?
a. Amount of rainfall and level of water in a lake.
b. Number of lights left on each day and the amount of electric bill.
c. Increase of warm, sunny days and the number of ice cream trucks visible.
d. Number of hours worked and how much money is made.
17. Teresa records the ages and weights of 12 children in her neighborhood. If she records this data in a
scatterplot, what type of correlations will she most likely see?
18. When evaluating data on a scatter plot, what can be used to make predictions about the future?
a. interpolation
b. extrapolation
c. causation
d. correlation coefficient
The coaches of a group of debate teams answered a survey about hours of debate, team practice and
number of team wins. The graph shows the results of this survey.
19. The scatterplot indicates which of the following?
A a positive correlation
C no correlation
B a negative correlation
D a parallel correlation
20. Based on these results, if a team practices 4 hours per week
next season, which is the best estimate of the number of debates
the team can expect to win?
A 20
B 16
C 12
D 1