Understanding Percentages
Understand the per cent symbol (%); know that per cent means ‘number of parts per hundred’; write percentages as a fraction with denominator 100 and as a decimal
What a learner can do afterwards
- Write 35% as 35/100 and as 0.35
- Shade 40% of a 10×10 grid and write the fraction 40/100
- Explain that 100% means the whole, 50% means half
The lesson
The symbol % is called percent. Percent means 'out of 100.' When you see 35%, it means 35 out of every 100 equal parts. You already know how to write hundredths as decimals, so percent gives you a new way to write the same amount.
Look at 35%. Since percent means out of 100, you can write it as the fraction 35/100. A fraction with 100 on the bottom is also a decimal with two digits after the point, so 35/100 is the same as 0.35.
100% means the whole thing, all 100 parts. 50% means half, since 50 is half of 100. Whenever you see percent, ask yourself: how many parts out of 100?
Percent means out of 100: write it as a fraction over 100, then as a decimal by counting two places.
Watch it
Where it sits
Where this leads
Jobs that lean on this skill. Follow one to see everything it is built on.
8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.