What is the percent strength (w/w) of a drug if 50mg of a drug is added to 150mg of diluent?

Question

Pharmacy Technician calculations question

Answer 1

%-(w/w) = (weight of drug / weight of solution) x 100%

weight of solution = weight of drug + weight of diluent (solvent) = 50 + 150 = 200 mg

%-(w/w) = (50 mg / 200 mg) x 100% = 25%-(w/w)