Add and Subtract Rational Expressions
-Doctors Use the Rational Expression $$\frac { \mathrm { DA } } { \mathrm { A } + 12 }$$

question 23

Multiple Choice

Add and Subtract Rational Expressions
-Doctors use the rational expression $$\frac { \mathrm { DA } } { \mathrm { A } + 12 }$$ to determine the dosage of a drug prescribed for children. In this expression, A = child's age and D = adult dosage. What is the difference in the child's dosage for an 8-year-old child and a 4-year-old child? Express the answer as a single rational expression in terms of D.

• A) \(\frac { 3 } { 20 } \mathrm { D }\)
• B) \(\frac { 1 } { 5 } \mathrm { D }\)
• C) \(\frac { 1 } { 4 } \mathrm { D }\)
• D) \(14 \mathrm { D }\)

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Definitions:

Genetic Link

A connection between certain genes and specific traits or diseases.

Cones

Photoreceptor cells in the retina of the eye that function best in relatively bright light and enable the perception of color.

Visual Acuity

The clarity or sharpness of vision, often measured as the ability to discern letters or numbers at a given distance.

Wavelength

The distance between corresponding points of two consecutive waves, commonly associated with the characteristics of waves in physics, such as light and sound.