Wind chill is a measure of how cold people feel when exposed to wind outside. A good estimate for wind chill can be found using this calculation: $$W=T-0.7\cdot S$$ Where $W$ represents the wind chill, $T$ represents air temperature measured in degrees Fahrenheit $(^{\circ}F),$ and $S$ represents wind speed measured in miles per hour (mph).

Suppose the air temperature is $36^{\circ}F$ and the wind speed is $18$ mph. Which of the following is closest to the approximate wind chill?

Answer: B

Concepts:substitutiondecimalestimation

Difficulty rating: 450

AMC 8AMC 10AMC 12AIME

Video solution:

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Written solution:

Using the formula, we can calculate the wind chill to be $$\begin{align*} 36 - 0.7 \cdot 18 &= 36 - 12.6 \\ &=23.4. \end{align*}$$

Thus, B is the correct answer.