Question

The doctor orders 1.5 mg/kg of a drug for a child weighing 95 lb. The drug is available as 125 mg/2 mL. How manymL must you administer? (round to the hundredths place)

Answer 1

We are asked to determine the volume of a drug to be administered. To do that we will convert the mass from pounds to kilograms. We will use the following conversion factor:

`1kg=2.2lb`

Now, we multiply by the conversion factor:

`95lb*(1kg)/(2.2lb)=43.1kg`

Now, we multiply the mass by the rate of mg per kg:

`(15(mg)/(kg))(43.1kg)=646.5mg`

Now we use the rule of 3 to determine the amount of mL required:

`\begin{gathered} 125mg\rightarrow2mL \\ 645.5mg\rightarrow x \end{gathered}`

Now, we cross multiply:

`125mg(x)=(2mL)(645.5mg)`

Now, we divide both sides by 125mg:

`x=((2mL)(645.5mg))/(125mg)`

Solving the operations:

`x=10.33mL`

Therefore, 10.33mL are required.