Convert between percents, fractions, and decimals
Percents, fractions, and decimals are three different ways to talk about the same value. They're like speaking three different languages for numbers! Learning to translate between them is a superpower for solving real-world math problems. ↔️
Do this: Read the concept below, then try the quiz or activity.
Lesson 84 of 215
Concept
Percents, fractions, and decimals are all ways of representing parts of a whole. Understanding how to convert between them is a fundamental math skill.
The Key Idea: "Percent" means "out of 100". * 50% means 50 out of 100. * 25% means 25 out of 100.
1. Percent to Decimal This is the easiest conversion! Just move the decimal point two places to the left and remove the % sign. * 75% -> 75. -> .75 -> 0.75 * 8% -> 8. -> .08 -> 0.08 (add a zero placeholder) * 125% -> 125. -> 1.25 -> 1.25
2. Decimal to Percent Do the opposite: move the decimal point two places to the right and add a % sign. * 0.35 -> 3.5 -> 35. -> 35% * 0.9 -> 9. -> 90. -> 90% (add a zero) * 1.5 -> 15. -> 150. -> 150%
3. Percent to Fraction Put the percent number over 100 and simplify. * 40% = 40/100 -> (divide by 20) -> 2/5 * 25% = 25/100 -> (divide by 25) -> 1/4
4. Fraction to Percent
This is the trickiest. First, convert the fraction to a decimal, then convert the decimal to a percent.
* Convert 3/4 to a percent:
1. Fraction to Decimal: 3 ÷ 4 = 0.75
2. Decimal to Percent: Move the decimal two places right -> 75%* Shortcut: If you can make the denominator 100, the numerator is the percent!
* 3/5 = (3x20)/(5x20) = 60/100 = 60%Common Conversions to Memorize: * 1/2 = 0.5 = 50% * 1/4 = 0.25 = 25% * 3/4 = 0.75 = 75% * 1/5 = 0.2 = 20% * 1/10 = 0.1 = 10%
Try it
Practice: Convert between percents, fractions, and decimals.