If you want to get the unknown number, you should know the known number first.

如果要想求出未知数，你首先得知道已知数。

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A known number rectangular area is a Y square centimetre, one side is long for X is that this rectangular circumference is several centimetres centimetre.

已知一个长方形的面积为Y平方厘米，一边长为X厘米，则这个长方形的周长为几厘米。

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By report, US na German is a known number of in the world only's develop this strange disease clan, but the whole world "nothing fingerprint people" final total does not exceed 20!

据悉，美娜德一家是世界上惟一已知的患有这种怪病的家族，而全世界的“无指纹人”总计不超过20个！

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Diakite,who is also known as Toumba, escaped the attack and is still at large with an unknown number of soldiers from the presidential guard.

VOA: standard.2009.12.07

Agricultural villages will have existed all over the place in the late Stone Age, in the Neolithic Period, as it is known. But there is a difference and the critical difference is that a city contains a number of people who do not provide for their own support.

农业村庄在石器时代后期,以及新石器时代随处可见,但二者是有区别的,最重要的区别在于,城市能容纳,相当数量,无需自给自足的人口

耶鲁公开课 - 古希腊历史简介课程节选

Missus Obama joked that if she had known, she would have picked a higher number.

VOA: special.2010.05.28

The highest known magic number for neutrons alone is 126.

ECONOMIST: Nuclear physics: Magical shell game | The

Pol Pot, once known as Brother Number One, died in a jungle hideout in 1998.

CNN: ASIANOW - TIME Asia | CAMBODIA: Will Justice Ever be Served?

The malware is known by a number of names and is contained in the setup.exe and autorun.ini files.

FORBES: IBM Distributes Malware-Infected USB Sticks At Security Conference