A nurse is preparing to administer acetaminophen 400 mg PO to an adolescent. Available is acetaminophen liquid 160 mg/5 mL. How many mL should the nurse administer? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)

To calculate the dosage of acetaminophen liquid required, one must use the formula: (desired dose / available dose) x volume of available dose. For the adolescent who needs 400 mg of acetaminophen, and with the available acetaminophen liquid concentration of 160 mg per 5 mL, the calculation would be: (400 mg / 160 mg) x 5 mL. This simplifies to 2.5 x 5 mL, which equals 12.5 mL. Answer: 13 mL (rounded off to the nearest whole number)