Pharmacy calculations worksheet with answers

Practice exercise (made-up values, not clinical guidance). A solution of potassium permanganate has a ratio strength of 1:10 000. How many milligrams m are in 1000 mL?

A solution is 5% w/v. You need 85 mg of the drug. Draw up the volume in the syringe: what volume V is that?

A solution has a ratio strength of 1:10 000. You need 0.22 mg. Draw up the volume in the 10 mL syringe: what volume V is that?

Practice exercise (made-up values, not clinical guidance). A vial contains ampicillin 1000 mg as a powder. The practice label says to add 3.5 mL of sterile water; the powder adds 0.5 mL to the volume. What is the concentration C in mg/mL after reconstitution?

Practice exercise (made-up values, not clinical guidance). You have 30 g of 5% coal tar ointment. How many grams m of 1% coal tar ointment must you add to make a 2% ointment? Round to the nearest whole gram.

Practice exercise (made-up values, not clinical guidance). You must prepare 200 mL of 15% dextrose by mixing 50% and 10% dextrose. How many mL V of the 50% solution do you need? Round to the nearest whole mL.