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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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