A nurse is preparing to administer quinapril 20 mg PO. Available is quinapril 40 mg tablets. How many tablets should the nurse administer? (Round the answer to the nearest tenth. Use a leading zero if it applies. Do not use a trailing zero.)

Calculation: Desired dose = 20 mg. Identify the available dose per tablet = 40 mg/tablet. Calculate the number of tablets to administer. Number of tablets = Desired dose (mg) / Available dose (mg/tablet) = 20 mg / 40 mg/tablet = 0.5 tablet. Rounded to the nearest tenth: 0.5.