A nurse is preparing to administer penicillin 250 mg IM. Available is penicillin 3 g/5 mL. How many mL 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: Identify the ordered dose and available concentration Ordered Dose: 250 mg Available Concentration: 3 g/5 mL = 3000 mg/5 mL Calculate the concentration per mL 3000 mg ÷ 5 mL = 600 mg/mL Calculate the volume to administer Volume (mL) = Ordered Dose ÷ Concentration Volume = 250 ÷ 600 Volume = 0.4167 mL Round to the nearest tenth = 0.4 mL