Question

A solution for direct IV bolus injection contains 125 mg of drug in each 25 mL of injection. What is the concentration of drug in terms of μg/μL?

Answer 1

Answer:

The concentration of the drug is 5ug/uL

Step-by-step explanation:

The first step of the problem is the conversion of the quantities of the drug in mg and mL to ug and uL.

In a rule of three problem, the first step is identifying the measures and how they are related, if their relationship is direct of inverse.

When the relationship between the measures is direct, as the value of one measure increases, the value of the other measure is going to increase too.

When the relationship between the measures is inverse, as the value of one measure increases, the value of the other measure will decrease.

Unit conversion problems, like this one, is an example of a direct relationship between measures.

First step: Conversion of 125mg to ug

Each mg has 1,000ug. So:

1mg - 1,000ug

125mg - xug

x = 1,000*125

x = 125,000 ug

Second step: Conversion of 25 mL to uL

Each mL has 1,000uL. So:

1mL - 1,000uL

25mL - x uL

x = 25*1,000

x = 25,000uL

Concentration:

$C = \frac{125,000 ug}{25,000uL} = 5ug/uL$

The concentration of the drug is 5ug/uL