Pharmacy calculations worksheet with answers

Practice exercise (made-up values, not clinical guidance). How many g of dextrose are in 250 mL of 10% w/v solution? Find m.

Practice exercise (made-up values, not clinical guidance). Express the ratio strength 1:2 000 as a percentage strength p (% w/v).

A solution has a ratio strength of 1:1000. You need 0.13 mg. Draw up the volume in the 1 mL syringe: what volume V is that?

Practice exercise (made-up values, not clinical guidance). A vial of penicillin G contains 5 000 000 units. Its practice label gives three strengths (see the table). You add 8.2 mL of diluent. The prescribed dose is 750 000 units. What volume V do you draw up? Round to one decimal place.

A vial holds 1000 mg of powder. You add 3.8 mL of diluent, and the powder adds 0.2 mL of volume. The prescription is 125 mg. Draw up the dose: what volume V do you give?

Practice exercise (made-up values, not clinical guidance). You must prepare 250 mL of 45% ethanol from a 90% stock and purified water. How many mL V of water do you need? Round to the nearest whole mL.