PSAT Math Multiple-Choice Question 588: Answer and Explanation

Question: 588

The formula used by the National Weather Service to calculate wind chill in degrees Fahrenheit is:

T represents the air temperature in degrees Fahrenheit, and V represents the wind velocity in miles per hour.

Which of these is an accurate statement about the relationship between wind chill and temperature?

The relative impact on wind chill of a particular increase in wind speed is more significant at lower wind speeds than at higher wind speeds.

Wind chill has an impact on the relative temperature feeling only at temperatures greater than or equal to 35.75 degrees Fahrenheit.

Wind chill and temperature are inversely related to one another.

• A. I only
• B. II only
• C. I and II only
• D. II and IIII only

Correct Answer: A

Explanation:

(A) Choice I is correct. Since the velocity is raised to a fractional exponent, the impact of a certain amount of wind speed increase is more significant at lower wind speeds than at higher wind speeds. Choice II is not correct. Wind chill still has an impact when the temperature is less than 35.75 degrees Fahrenheit since this number is a constant, not a minimal temperature. Choice III is not correct. As temperature increases, the perceived temperature due to wind chill also increases.