Question

It is important to know the appropriate dose of ibuprofen for a child so that you are ready in the case of high fever. The dosing guidelines state that children should be given 8mg/kg. Determine the dose of ibuprofen needed for a 2 ½ year old weighing 28 pounds. Round your final answer to the nearest whole number and make sure to state your units to earn full credit! (Recall: 1 kg = 2.2 lb)

Answer 1

Answer:

102 mg

Step-by-step explanation:

Let's convert 28 pounds to kgs.

Since 1 kg = 2.2 pounds, we can find:

$\frac{1Kg}{2.2Pounds}=\frac{xKg}{28Pounds}\\1*28=2.2x\\28=2.2x\\x=\frac{28}{2.2}\\x=12.73$

So 28 pounds is 12.73 Kg

Since 8mg is given per kg, for 12.73 kg, the amount given should be:

12.73 * 8 = 101.84

Rounded to nearest whole number, that is, 102 mg

Answer 2

Answer:

102 mg

Step-by-step explanation:

First, find the weight, in kilograms, of a 2 ½ year old child weighing 28 pounds.

1 kg = 2.2 pounds

x kg = 28 pounds

Write a proportion

$\dfrac{1}{x}=\dfrac{2.2}{28}$

Cross multiply

$2.2x=28\\ \\22x=280\ [\text{Multiply by 10}]\\ \\x=\dfrac{280}{22}=\dfrac{140}{11}=12\dfrac{8}{11}\ kg$

Now, the dosing guidelines state that children should be given 8mg/kg. So,

8 mg - 1 kg

y mg - $\dfrac{140}{11}\ kg$

Write a proportion

$\dfrac{8}{y}=\dfrac{1}{\frac{140}{11}}$

Cross multiply

$y=8\cdot \dfrac{140}{11}=\dfrac{1,120}{11}=101\dfrac{9}{11}\approx 102\ mg$