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:
The concentration of the drug is 5ug/uL