上下(shànɡxià)？左右(zuǒyòu)？前后(qiánhòu)？ Expressing an “Approximate Number” in Mandarin
If you need to express an “Approximate Number” in terms of time, weight, age, or any other term that involves a number, there are a number of ways to do it in Mandarin. This is a fundamental and important language point in Chinese daily life, and is even taught in the elementary level. There are many ways to express an “Approximate Number”, and below are some of the most frequently used ways by native Mandarin speakers:
Structure  Explanation  Example  
1.  Number A + Number B  (1) To use two adjacent numbers to show an uncertain number that may be the first (Num. A) or the second (Num. B)
(2) Generally, the sequence is from the lower number to the higher one. 
我叫了两三次，他都不理我。
（Wǒ jiàole liǎnɡsān cì，tā dōu bù lǐ wǒ.） I’ve called him two or three times, but he didn’t answer me anyway. 
2.  Number + Measure word + 左右/上下  (1) To denote a number that could be either larger or smaller than the given number.
(2) 上下(shànɡxià)：Mainly used to refer to age, it can’t be used for time and distance. 左右(zuǒyòu)：there are no limits to its usage. 
(1) 从我家到学校开车三十分钟左右。
(Cónɡ wǒ jiā dào xuéxiào kāichē sānshí fēnzhōnɡ zuǒyòu.) It will take about 30 minutes to drive from my house to the school. (2) 那位大爷看起来六十岁上下/左右。 (Nàwèi dàye kàn qǐlai liùshí suì shànɡxià/zuǒyòu.) That old person looks like about 60 years old. 
3.  Number + Measure + 多  (1) To indicate a number that is more than the given number.
(2) Usually the number must be single place or multidigit with single place. (3) Measure words can be “个”, the metrology measure word, the time measure word, or “倍” etc. 
我买了四斤多的牛肉。
(Wǒ mǎile sì jīn duō de niúròu.) I’ve bought more than 2 kilos beef.
工资涨了两倍多。 (Gōnɡzī zhǎnɡle liǎnɡ bèi duō.) The salary has more than doubled. 我做了两个多小时的作业。 (Wǒ zuòle liǎnɡ ɡè duō xiǎo shí de zuòyè.) I’ve done homework for more than two hours.

Number+ 多+ Measure  (1) To indicate a number that is more than the given number.
(2) Usually the number must be ten or integers that ends with a zero. 
他们班里有五十多个女生。
(Tāmen bānlǐ yǒu wǔshí duō ɡè nǚshēnɡ.) There are more than 50 girls in their class. 

4.  Number + Measure + 来+Noun./ Adjective.  (1) To indicate a number that is close to the given number.
(2) Usually the measure word can be only “个” or the metrology measure word. (3) The succeeding nouns or adjectives can’t be left out. 
他一直在门口等你，等了差不多三个来小时。
(Tā yìzhí zài ménkǒu děnɡ nǐ，děnɡle chàbùduō sān ɡè lái xiǎoshí.) He has been waiting for you at the gate for about three hours.
那袋大米有四斤来重。 (Nàdài dàmǐ yǒu sìjīn lái zhònɡ.) That bag of rice weighs about 2 kilos. 
Number +来+Measure  (1) To indicate a number that is
close to the given number. (2) Usually the number must be ten or integers that ends with a zero. 
这些书一共有五十来斤。
(Zhèxiē shū yíɡònɡ yǒu wǔ shí lái jīn.) These books weigh about 25 kilos in total. 

5.  近(jìn)+Numeral Phrase  (1) To indicate a number that is
close to the given number. (2) Usually the given number is much bigger. 
这次有近百人参加了会议。
(Zhècì yǒu jìn bǎi rén cānjiā le huìyì.) This time nearly one hundred people attended the meeting. 
6.  上 + Digit Word  To indicate a large number.  我的衣柜里有上百条裙子。
(Wǒde yīɡuì lǐ yǒu shànɡ bǎi tiáo qúnzi.) There are nearly one hundred skirts in my wardrobe. 
7.

Number + 把  (1) To indicate a number that is close to the given number.
(2) The number should be a Digit Word, like, “百”，“千”，“万”etc. 
他一个月能赚万把块吧。
(Tā yíɡèyuè nénɡ zhuàn wàn bǎ kuài bɑ.) He can make nearly 10 thousand yuan each month. 
Measure+把  (1) To indicate a number that is close to the measure word before.
(2) Without number before the measure word. 
我们班里有个把学生学习很不认真。
(Wǒmen bānlǐ yǒu ɡèbǎ xuéshenɡ xuéxí hěn bù rènzhēn.) There are several students in our class who don’t treat study seriously. 

8.  Time point/Time word +前后(qiánhòu)  (1) To denote a number that is larger or smaller than the given number.
(2) Can’t be used after a phrase that denotes a time period. 
他昨天十点前后回家的。
(Tā zuótiān shídiǎn qiánhòu huíjiā de.) He came back home around 10 p.m. 
9.  大概(dàɡài) / 大约(dà yuē) + Number + Measure  To indicate an approximate number.

从这儿到北京大约/大概要五个小时。
(Cónɡ zhè’r dào BěiJīnɡ dà yuē/dàɡài yào wǔ ɡè xiǎoshí.) It will take about 5 hours from here to Beijing. 
10.  至多(zhìduō)/最多(zuì duō) + Number + Measure  To indicate the maximum.

车子至多/最多坐四个人。
(Chēzi zhìduō/zuìduō zuò sì ɡè rén.) The car can seat 4 people at most. 
至少(zhìshǎo) /最少(zuì shǎo )+ Number+ Measure  To indicate the minimum.  论文至少/最少两万字。
(Lùnwén zhìshǎo/zuìshǎo liǎnɡ wàn zì.) The paper can’t be less than 20 thousand letters. 
These are some of the more common ways to express an “Approximate Number” in Mandarin. There are actually even more ways to do so, but by mastering the rules given here in this article, and by practicing these constantly in your daily conversations, this knowledge will be more than sufficient for you to make yourself understood when you want to talk about “Approximate Numbers” to a native Chinese speaker.