2.5 Hours to Minutes: A Real-Life Example (from Nursing)

This article delves into a facet of nursing that involves mathematical skills, specifically the conversion between hours and minutes. The example illustrates the importance of converting hours into minutes for dosage calculations.

300 ml of Fluid in 2.5 Hours: Example from Nursing Practice


Nursing is a noble profession that demands empathy, patience, and, surprisingly, some math skills too. Among the crucial applications of math in nursing is the conversion of time, weight, volume, and other units for dosage calculations. Let’s delve into a practical example.

Example: 2.5 Hours to Minutes

Imagine a scenario where a nurse needs to administer an intravenous infusion of 300mL of fluid over 2.5 hours. The task at hand involves calculating the optimal flow rate, measured in drops per minute.

Animated gif of a drip chamber with falling drops

Assume 1 mL equals 20 drops1, the total drops for 300ml would be: 300 × 20 = 6000 drops. These drops must be delivered into the patient’s vein over 2.5 hours. Knowing that 1 hour consists of 60 minutes, we find that 2.5 hours equals: 2.5 × 60 = 150 minutes. To deliver 6000 drops in 150 minutes, the nurse needs to set the IV bag at: 6000 / 150 = 40 drops per minute.

1 Depending on drip chamber type, there can be different amount of drops in 1ml, e.g. 10, 12, 15, 20 or 60 drops per mL.


Mastering the conversion of time units, especially from hours to minutes, is a crucial skill for every nurse. Additionally, many other professions require proficiency in converting units of length, volume, time, weight, and more. This knowledge is imparted during your math and science lessons, proving its significance not just in academics but also in real-life applications.

Check the facts!

For preparing this article we used information from the “Nursing skills” (Open Resources for Nursing (Open RN); Ernstmeyer K, Christman E, editors. Nursing Skills [Internet]. Eau Claire (WI): Chippewa Valley Technical College; 2021. Chapter 5 Math Calculations. Available from National Library of Medicine.

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