identical twins come from the same egg and hece are of the same sex.fraternal twins have a 50-50 chace of being of the same sex.among twins,the probobility of a fraternal set is p and an indentical set is q=1-p.if the next set of twins are of the same sex,what is the probobility that they are identical
答案是2q/(1+q)
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Post By：2004/11/17 23:02:33 [显示全部帖子]
