Cowling rule is another method for determining the dosage of a drug to prescribed to a child. For this rule, the formula
gives the child's dosage d, Where D is the adult dosage and a is the age of the child in years. If the adult dosage of a drug is 600 milligrams and a doctor uses this formula to determine that a child's dosage is 200 milligram, then how old is the child?
This provides an example of using Cowling's rule to determine the age of a child with a specified dosage.