# Lesson Worksheet: Correlation Mathematics • 8th Grade

In this worksheet, we will practice dealing with linear correlation and distinguishing between different types of correlation.

**Q3: **

The scattergraph shows the average gestation period, measured in days, against the average brain mass of an adult, measured in grams, for 13 species of mammals.

What type of correlation appears to exist between the gestation period and the brain mass?

- Aa negative linear correlation
- Ba positive linear correlation

What is the correct interpretation of this relationship?

- AIn general, as the gestation period increases, the brain mass decreases.
- BA greater brain mass leads to a longer gestation period.
- CIn general, as the gestation period increases, so too does the brain mass.
- DIn general, as the gestation period decreases, the brain mass increases.

**Q6: **

Suppose variable is the speed of a car and variable is the car’s travel time to its destination. You suspect that if the car decreases its speed, its travel time to the destination increases. Does this follow a positive correlation, negative correlation, or no correlation?

- Anegative correlation
- Bno correlation
- Cpositive correlation

**Q7: **

Suppose variable is the speed of a train and variable is the time for the train to get to the station. You suspect that the more the train increases its speed, the less time it takes to get to the station. Does this follow a positive correlation, negative correlation, or no correlation?

- Anegative correlation
- Bpositive correlation
- Cno correlation

**Q9: **

What type of correlation does the graph show?

- Anegative correlation
- Bno correlation
- Cpositive correlation

**Q10: **

What type of correlation exists between the two variables in the shown scatterplot?

- AA negative linear correlation
- BA positive linear correlation
- CNo correlation

**Q11: **

The following scatter diagram shows the scores of two tests for a class of 26 students. What type of correlation does the graph show?

- Anegative correlation
- Bno correlation
- Cpositive correlation

**Q12: **

The following scatterplot shows the heights and weights of 24 students in a class. What type of correlation does this graph show?

- Ano correlation
- Ba positive correlation
- Ca negative correlation

**Q13: **

What type of linear correlation might exist between the time a student takes to travel to school and the age of the student?

- ANo correlation
- BPositive correlation
- CNegative correlation

**Q15: **

Does all bivariate data suggest a linear relationship?

- AYes. Otherwise, drawing a scatter plot would not be possible.
- BNo, because some variables are not correlated linearly or at all.
- CNo, because lines of best fit work for nonlinear relationships as well.
- DYes, that is what “bivariate” means.

**Q16: **

Suppose variable is the number of hours you spent studying, and variable is your grade in the final exam. You suspect that the more hours you spend studying, the higher your grade is. Does this follow a positive correlation, a negative correlation, or no correlation?

- Ano correlation
- Bpositive correlation
- Cnegative correlation

**Q18: **

Which of the following correlation coefficients represents the strongest negative relationship between two variables?

- A
- B
- C
- D
- E

**Q19: **

Which of the following scattergraphs represents the strongest positive correlation between two variables?

- A
- B
- C
- D
- E

**Q22: **

Which of the following scattergraphs represents a strong correlation between two variables?

- AFigure 1
- BFigure 2

What type of correlation exists between the two variables in the previous scattergraphs?

- AA positive correlation
- BA negative correlation

**Q24: **

Which of the following correlation coefficients represents the weakest positive relationship between two variables?

- A0.74
- B0.18
- C0.15
- D0.91
- E0.32