多
duō
Indicating a number in excess
多 after a number means "-odd" — thirty-something, twenty-plus.
Number + 多 (+ Measure Word + Noun)
How it works
三十多岁 is thirty-something years old; 一百多个人 is a hundred-odd people.
Where 多 goes depends on the number. After a round number it comes before the measure word: 二十多个. After a non-round one it comes after: 三个多小时 (three-odd hours).
Examples
tā sān shí duō suì
他三十多岁。
He's thirty-something.
zhè lǐ yǒu yì bǎi duō gè rén
这里有一百多个人。
There are a hundred-odd people here.
wǒ děng le sān gè duō xiǎo shí
我等了三个多小时。
I waited over three hours.