Which of the following pairs is the most likely to exhibit a direct relationship?
a. The price of gasoline and the amount of gasoline that people purchase.
b. Cholesterol levels and the likelihood of developing heart disease.
c. Outdoor temperature and heating oil sales.
d. Annual income and weekly pawn shop visits.
The correct answer and explanation is :
The correct answer is:
b. Cholesterol levels and the likelihood of developing heart disease.
Explanation:
A direct relationship means that as one variable increases, the other also increases. In other words, both variables move in the same direction.
Among the given options, cholesterol levels and the likelihood of developing heart disease have a clear and well-documented direct relationship. As cholesterol levels in the blood increase, the risk of developing heart disease also increases. High cholesterol can lead to the buildup of fatty deposits in the arteries, which may narrow or block blood flow, leading to conditions like heart attacks or strokes. Numerous scientific studies have established this link, making it a strong example of a direct relationship.
Why the other options are incorrect:
- (a) The price of gasoline and the amount of gasoline that people purchase: This represents an inverse (negative) relationship because as the price of gasoline increases, people generally buy less gasoline (assuming demand responds to price changes).
- (c) Outdoor temperature and heating oil sales: This is also an inverse relationship because as temperature rises, the need for heating oil decreases. People use less heating oil in warmer weather.
- (d) Annual income and weekly pawn shop visits: This likely represents an inverse relationship as well. Generally, people with higher incomes are less likely to visit pawn shops regularly, while those with lower incomes may rely on pawn shops more frequently.
Thus, the only pair that demonstrates a direct relationship is cholesterol levels and the likelihood of developing heart disease.
