Lesson overview
Percentages in Medication Math
Ready when you are
Start with short teaching slides, then answer the lesson questions. Your progress stays on this browser.
Learning outcomes
What you will learn
- read a percentage as an amount out of 100
- move between a percentage, decimal and simple fraction
- explain what w/v, v/v and w/w mean
- convert a % w/v strength into mg/mL
- use the ×10 shortcut only after understanding why it works
Clinical connection
Why this matters
Percentage strengths can appear in medication and solution calculations. If the percentage or its basis is read incorrectly, every calculation that follows can be wrong.
Quick concept
Percent means per 100 — then check what the percentage is measuring
A percentage is an amount out of 100. On a medicine or solution label, the letters after the percentage identify the concentration basis. For a weight-in-volume strength, 1% w/v means 1 g in 100 mL, which is 10 mg/mL. The same shortcut must not be applied blindly to v/v or w/w strengths.
Formula
for % w/v: 1% = 1 g/100 mL = 10 mg/mL
Worked example
Educational example: a fictional solution is labelled 2% w/v.
2 g/100 mL = 2000 mg/100 mL = 20 mg/mL
Answer: 20 mg/mL
A percentage strength describes concentration; it does not select a dose, route, dilution or administration plan. Verify the exact concentration basis on the current product or learning question before doing any downstream calculation.
Lesson plan
How the lesson works
- 1
Learn
Short teaching slides explain one idea at a time with plain-language examples.
- 2
Practise
Answer calculation or scenario questions and receive immediate feedback.
- 3
Finish
Complete the lesson check and save your learning progress on this browser.
Keep going
Learn, practise, apply and check this skill
Use the page that matches what you need next. Each resource has a different job, so the lesson can stay focused on teaching the skill.
Practise
Medication percentage calculation practice
Practise percentage-decimal-fraction conversions and percentage-strength questions across four levels.
Understand
Percentage strength explained
Review w/v, v/v and w/w notation, % w/v to mg/mL and common interpretation errors.
Check
mg to mL Calculator
Use dose-to-volume arithmetic only after the medication concentration has already been verified in mg/mL.
Apply
Medication & IV Safety cases
Apply concentration-reading and medication-maths skills inside evolving clinical scenarios.