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
1 · Read
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.
2 · Watch
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Where it sits
Where this leads
Jobs that lean on this skill. Follow one to see everything it is built on.
14 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.