Fractions, percentages, multiples: 分之, 百分之, 倍
数词 / numerals
Tone colorsā tone 1á tone 2ǎ tone 3à tone 4a neutral
Chinese says fractions backwards compared to English: denominator first, then 分之, then the numerator. 三分之一 = one third (literally "of three parts, one").
Percentages follow the same logic: 百分之 + number. 百分之六十 = 60%.
Multiples use 倍 (bèi): A 是 B 的两倍 (A is twice B). 增加了一倍 = has doubled (increased by 100%).
Examples
地球上三分之二是水。
Dìqiú shang sān fēn zhī èr shì shuǐ.Two thirds of the Earth is water.
百分之八十的人支持垃圾分类。
Bǎi fēn zhī bāshí de rén zhīchí lājī fēnlèi.80% of people support rubbish sorting.
这个城市的汽车比十年前多了两倍。
Zhège chéngshì de qìchē bǐ shí nián qián duō le liǎng bèi.This city has three times as many cars as ten years ago.
今年的用电量是去年的一半。
Jīnnián de yòngdiànliàng shì qùnián de yíbàn.This year's electricity use is half of last year's.
Common mistakes
✗ 一分之三 for "one third" → ✓ 三分之一。
✗ 六十百分之 → ✓ 百分之六十。
Careful: 多了两倍 = three times as many (two times more added), while 是……的两倍 = twice as many.