Final answer:
To find the correct dosage for a 41 lb child, convert the weight to kilograms by dividing by 2.20462, resulting in 18.597 kg. Then, multiply by the dosage rate of 3 mg/kg to get a final dosage of approximately 55.791 mg.
Step-by-step explanation:
The dosage of an asthma drug is calculated based on the child's weight. First, we need to convert the child's weight from pounds to kilograms because the dosage is given in milligrams per kilogram. Since 1 kilogram is equal to 2.20462 pounds, we divide the child's weight in pounds by 2.20462 to get their weight in kilograms.
For a 41 lb child:
Weight in kg = 41 lb ÷ 2.20462 = 18.597 kg
Now, using the dosage of 3 mg/kg, we multiply the child's weight in kilograms by the dosage per kilogram:
Dosage in milligrams = 3 mg/kg × 18.597 kg
When you calculate this, you get 55.791 mg. Therefore, the correct dosage for a 41 lb child is approximately 55.791 milligrams.