Interpreting Correlations: TEAS Practice Question with Answer & Explanation

Understanding Negative Correlation

On the TEAS Math section, you are expected to interpret the relationships between two variables. A negative correlation (also known as an inverse relationship) occurs when two variables move in opposite directions. As one variable goes up, the other goes down—and vice versa.

Why Choice B is Correct

In the scenario "As the speed of a vehicle increases, the remaining distance to its destination decreases," we see two variables:

1. Speed (Increasing)
2. Distance to destination (Decreasing)

Because these variables are moving in opposite directions (up and down), this is a classic example of a negative correlation. The faster you drive, the less distance you have left to cover.

Analysis of the Incorrect Options

• Choice A: "As a person's age increases, the amount of time they spend sleeping increases." This describes a positive correlation because both variables are moving in the same direction (increase/increase). (Note: While biologically infant sleep patterns differ, mathematically, this describes a positive trend).
• Choice C: "As the amount of rainfall increases, the height of the water in a reservoir increases." This is a positive correlation. When one variable goes up, the other follows.
• Choice D: "As the number of study hours increases, a student's test score remains constant." This describes zero correlation or no relationship, as the change in one variable has no effect on the other.

TEAS Concept: Correlation Types

When preparing for the TEAS, remember these three primary types of relationships:

• Positive Correlation: Variables move in the same direction (both up or both down).
• Negative Correlation: Variables move in opposite directions (one up, one down).
• Zero Correlation: There is no visible trend or relationship between the variables.

Nursing Application

In healthcare, understanding correlations is vital. For example, there is often a negative correlation between physical exercise and resting heart rate (as exercise frequency increases, resting heart rate typically decreases). Conversely, there is often a positive correlation between high sodium intake and blood pressure levels.

Memory Tip

Think of a negative correlation like a seesaw. When one side goes up, the other side must go down. Think of a positive correlation like an elevator; both variables travel up to the top floor or down to the lobby together.