Practice Solutions

Weak negative correlation. As the distance hiked increases, the volume of liquid in the canteen decreases. $(\mathrm{distance} \mathrm{hiked}, \mathrm{volume} \mathrm{of} \mathrm{liquid})$

No correlation. There is no relationship between the size of a person’s hand and the price of milk.

Strong negative correlation. As the outside temperature increases, heating costs decrease. $(\mathrm{outside} \mathrm{temperature}, \mathrm{heating} \mathrm{cost})$

Strong positive correlation. As the time spent reading increases, a person’s vocabulary size increases. $(\mathrm{time} \mathrm{reading}, \mathrm{vocabulary} \mathrm{size})$

Weak positive correlation. As rainfall amounts increase, the number of cars washed increases. $(\mathrm{rainfall}, \mathrm{number} \mathrm{of} \mathrm{cars} \mathrm{washed})$

6. The amount of time a person spends looking at a screen and the total number of steps they take during a day.

Negative correlation. As the amount of time a person spends looking at a screen increases, the number of total steps they take decreases. $(\mathrm{screen} \mathrm{time}, \mathrm{number} \mathrm{of} \mathrm{steps})$

7. The number of hours a class studies and their exam score.

Positive correlation. As the number of hours spent studying increases, the exam score increases. $(\mathrm{hours} \mathrm{studied}, \mathrm{exam} \mathrm{score})$

8. The number of products sold and a company’s revenue (the total money earned).

Positive correlation. As the number of products sold increases, the company revenue increases. $(\mathrm{products} \mathrm{sold}, \mathrm{revenue})$  

9. A car’s engine size and its gas mileage (amount of gas used per mile).

Negative correlation. As a car’s engine size increases, its gas mileage decreases. $(\mathrm{engine} \mathrm{size}, \mathrm{gas} \mathrm{mileage})$

10. The number of letters in a town’s name and the number of pets a person owns.

No correlation. There is no relationship between the number of letters in a town name and the number of pets a person owns.

11. The age of a car (excluding classic and collector’s cars)  and its resale value.

Negative correlation. As the car’s age increases, its resale value decreases. $(\mathrm{age} \mathrm{of} \mathrm{car}, \mathrm{resale} \mathrm{value})$

12. The distance a person runs and the amount of calories burned.

Positive correlation. As the distance a person runs increases, the calories burned increases. $(\mathrm{distance} \mathrm{ran}, \mathrm{calories} \mathrm{burned})$