Several different formulas have been proposed for determining the appropriate dose of a drug for a child in terms of the adult dosage. Suppose that A milligrams (mg) is the adult dose of a certain drug and C is the appropriate dosage for a child of age N years. Then Cowling’s rule says that

while Friend’s rule says that

Exercises 46 through 48 require these formulas.

Assume an adult dose of A = 300 mg, so that Cowling’s rule and Friend’s rule become functions of the child’s age N. Sketch the graphs of these two functions.

1 - (N+) A 24 C =