PSAT Math Multiple-Choice Question 388: Answer and Explanation

Question: 388

A researcher placed a fluid motion sensor in the Atlantic Ocean along the North Carolina coast to study the movement of the water. Every morning at 6:00 a.m., the movement of the water past the sensor was recorded. The figure above shows the results. Based on the data, which of the following would be a valid conclusion? (Assume that the summer months are June, July, and August and the winter months are December, January, and February.)

• A. In general, a greater volume of water moves per month in the Atlantic Ocean during the winter months than during the summer months.
• B. In general, a greater volume of water moves per month in the Atlantic Ocean during the summer months than during the winter months.
• C. In general, a greater volume of water moves per month in the oceans around the world during the winter months than during the summer months.
• D. In general, a greater volume of water moves per month in the oceans around the world during the summer months than during the winter months.

Correct Answer: A

Explanation:

A

Difficulty: Easy

Getting to the Answer: The question states that the data were collected in the Atlantic Ocean, so any conclusion drawn can be generalized only to that particular geographic region. Eliminate (C) and (D). The question defines the winter months as December, January, and February. According to the data, a greater volume of water moved during those months than during the summer months of June, July, and August, so (A) is correct.