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Problem 181

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Investigating in how many ways objects of two different colours can be grouped

Having three black objects B and one white object W they can be grouped in 7 ways like this:

(BBBW)	(B,BBW)	(B,B,BW)	(B,B,B,W)	(B,BB,W)	(BBB,W)	(BB,BW)

In how many ways can sixty black objects B and forty white objects W be thus grouped?

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有关两种不同颜色的物体如何分组的研究

三个黑色物体B和一个白色物体W进行分组，有以下7种方式：

(BBBW)	(B,BBW)	(B,B,BW)	(B,B,B,W)	(B,BB,W)	(BBB,W)	(BB,BW)

六十个黑色物体B和四十个白色物体W进行分组有多少种方式？

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