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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