For a pump, which is programmed in millilitres per hour. Total volume ÷ time in hours. When the time is given in minutes, convert before dividing — not after.
Millilitres per hour
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Enter the volume and the time.
Sanity-check the answer. A maintenance infusion usually runs somewhere between 50 and 150 mL/hr. A result of 900 mL/hr should make you re-read the question before you trust it.