Body mass index (BMI)is a comparison of a person's body mass to his or her height. A high BMI can be an indicator of high body fat, which can lead to health problems. According to the American Heart Association, an adult is underweight if his or her BmI is less than 18.5, or overwieght if it is greater than or equal to 25.0. Which of the following number lines could be used to model a healthy BMI range for an adult?

Options

A.
B.
C.
D.

Answer

A

Explanation

Difficult:Medium:
Category: Heart of Algebra/ Inequalities
Strategic Advice: When you see phrasses like "less than " or ' greater", write an inequality to describle the situation. Then graph yout inequality on a number line by shading to the left for `lt or le` and shading to the right for `gt or ge`
Getting to the Answer: A person with BMI that is less than 18.5 is underweight. If b represenets BMI of an underweight person can be expressed as `blt18.5`, so draw an open dot at 18.5 and shade to the left. likewise, a person with a BMI that is greater than or equal to 25.0 is overweight, which can be expressed as `bgt25.0`. Draw a solid dot at 25 and shade to the right. The number line in choice B represents the combination of these inequalities, but be careful- that's not what the questions asks! The question asks for the healthy BMI range, so you're looking for the opposite of choice B- a solid dot at 18.5 an open dot at 25.0 and shaded between them, which is (A).