Module 1 - Basic Arithmetic Review¶
Overview¶
This module reviews the core arithmetic skills that underpin every nursing calculation you will encounter in clinical practice. Before calculating a drug dose or an IV flow rate, you need to be confident with the fundamentals covered here.
Work through each topic in order — each one builds on the last.
Learning Objectives¶
By the end of this module you should be able to:
- Perform operations with whole numbers, fractions, and decimals
- Round numbers correctly to the required decimal place
- Calculate percentages
- Recognize and apply patient safety rules around decimal notation
- Apply these skills to basic clinical scenarios
Topics¶
| Topic | Key Skills |
|---|---|
| Whole Numbers | Addition, subtraction, multiplication, division |
| Fractions | Simplifying, multiplying, dividing, adding |
| Decimals | Operations, comparing, leading and trailing zeros |
| Rounding | Nearest whole, tenth, hundredth — nursing standards |
| Percentages | Converting, calculating, IV concentrations |
Estimated Time¶
Approximately 1-2 hours including practice problems.
Clinical Relevance¶
Why This Matters
Every dosage calculation in this course reduces to basic arithmetic at the final step. A rounding error, a misplaced decimal point, or a percentage miscalculation can result in a patient receiving the wrong dose.
These are not abstract math skills — they are patient safety skills.
Before You Begin
Have a pen and paper ready. Attempt every practice problem by hand before checking the answer. Writing out each step builds the habit of showing your work — which is expected in clinical practice and on competency exams.
Patient Safety — Decimal Notation
Two rules you must know before any medication calculation:
- Always write a leading zero — 0.5 mg not .5 mg
- Never write a trailing zero — 5 mg not 5.0 mg
These rules exist because misread decimals are a leading cause of medication errors. They will be reinforced throughout this course.