Question

Youngs rule to calculate a child medicine dosage is c=na/n+12 where c is the child's dosage in mL, n is the child's age and A is the adult's dosage in mLA nurse gave an 8-year-old child a dose of 6 mL of medicine. What would be the adult equivalent of this dosage

Answer 1

$15ml$

1) Given that rule, we can write out the following for this case:

$\begin{gathered} C=\frac{nA}{n+12}= \\ \end{gathered}$

2) So let's plug into that the data:

$\begin{gathered} 6=\frac{8A}{8+12} \\ 8A=20\times6 \\ 8A=120 \\ \frac{8A}{8}=\frac{120}{8} \\ A=15 \end{gathered}$

Note that we have cross multiplied and then divided both sides by 8. So the dosage of an adult, according to this rule would be 15 ml