Rounding¶
Why Rounding Matters in Nursing¶
Calculations rarely produce clean whole numbers. Knowing when and how to round correctly is essential for safe medication administration. Rounding incorrectly — even by a small amount — can lead to under or overdosing.
The Basic Rounding Rule¶
Look at the digit immediately to the right of where you are rounding:
- If it is 5 or greater — round up
- If it is 4 or less — round down (keep the digit the same)
Rounding to the Nearest Whole Number¶
Look at the tenths place (first digit after decimal):
[3.7 \rightarrow 4] [3.4 \rightarrow 3] [12.5 \rightarrow 13]
Rounding to the Nearest Tenth¶
Look at the hundredths place (second digit after decimal):
[3.45 \rightarrow 3.5] [3.44 \rightarrow 3.4] [0.678 \rightarrow 0.7]
Rounding to the Nearest Hundredth¶
Look at the thousandths place (third digit after decimal):
[3.456 \rightarrow 3.46] [3.454 \rightarrow 3.45] [0.1255 \rightarrow 0.13]
Nursing Rounding Standards¶
Standard Practice
In most clinical settings:
- Oral medications — round to the nearest tenth (one decimal place)
- IV rates — round to the nearest whole number (mL/hr)
- Weight-based doses — round to the nearest tenth
- Pediatric doses — follow facility policy, often nearest hundredth
Always Check Facility Policy
Rounding rules can vary by institution and medication type. Always follow your facility's specific guidelines and double check high-alert medications with a second nurse.
Clinical Application¶
Example: A calculated dose is 3.678 mg. Following oral medication rounding standards, what do you administer?
Example: An IV pump requires a whole number rate. Your calculation yields 42.6 mL/hr. What do you set the pump to?
Practice Problems¶
Problem 1
Round 4.678 to the nearest tenth.
Answer
Look at hundredths place: 7 ≥ 5, round up. [4.678 \rightarrow 4.7]
Problem 2
Round 12.344 to the nearest hundredth.
Answer
Look at thousandths place: 4 < 5, round down. [12.344 \rightarrow 12.34]
Problem 3
A calculated oral dose is 5.549 mg. What do you administer?
Answer
Round to nearest tenth. Look at hundredths place: 4 < 5, round down. [5.549 \rightarrow 5.5 \text{ mg}]
Problem 4
An IV rate calculates to 87.5 mL/hr. What do you set the pump to?
Answer
Round to nearest whole number. Look at tenths place: 5 ≥ 5, round up. [87.5 \rightarrow 88 \text{ mL/hr}]
Problem 5
Round 0.0449 to the nearest hundredth.
Answer
Look at thousandths place: 4 < 5, round down. [0.0449 \rightarrow 0.04]
Common Mistake
Do not round multiple times in one calculation. For example, do not round an intermediate step and then round again at the end. Always carry full precision through the calculation and round only the final answer.