Mat 221 Cowling’s Rule

For this discussion I’m using Cowling’s Rule to find out a 5 year old child’s dosage of adult’s dosage (75mg) Tamiflu. After reading Elementary and Intermediate Algebra I have learned Cowling’s Rule is a formula which converts adult’s dosage into children’s dosage, using the age of the child. The literal equation will have three variables. The formula used is d = D (a + 1). The following is the variables for the literal equation: a = child’s age – 5 Years old
D = adult dose – 75 mg d = child’s dose
I have been assigned to calculate a 5-year-old child’s dose of tamiflu given that the adult dose is 75mg. d = D (a + 1) The Cowling’s Rule formula
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d = 75 (5 + 1) Substituted 75 for D and 5 for a.
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d = 75 (6) Add 5+1 inside parenthesis, equals 6.
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d = 450 Multiply 75 X 6 =450
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d = 18.75 Division is the last step in solving for the child’s dose.
The proper dose of tamiflu for a 5 year old child is 19mg.

For part B of the discussion I will determine a child’s age based on the dose of medicine he/she was prescribed. The same equation can be used, but I will be solving for another variables instead of d. The dose is 1200mg for an adult and 300mg for child. I will be solving the equation for a. The following is the variables for the equation: a = child’s age
D = adult dose – 1200 mg d = child’s dose – 300 mg d = D (a + 1) The Cowling’s Rule formula
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300= 1200(a + 1) Substituted 1200 for D and 300 for d.
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300(24) = 1200(a + 1)(24) Multiplied by 24 to eliminate denominator.
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7200 = 1200(a + 1) Multiplication on left side is
24 carried out.

7200= 1200 (a + 1) Divide both sides by 1200
1200 1200

6= a+1 One last stepped before the equation is solved.

6 – 1 = a + 1 – 1 Subtract 1 from both sides to isolate a.

5= A Now I have solved.
The dose of 300mg is intended for a five-year-old child. There are only one potential answer for this equation. Because of this the equation is a conditional equation.