8支排球隊(duì)中有2支強(qiáng)隊(duì)，任意將8隊(duì)平均分成兩組進(jìn)行比賽，求這2支強(qiáng)隊(duì)分在同一組的概率.

8支排球隊(duì)中有2只強(qiáng)隊(duì)，任意將8隊(duì)平均分成兩組比賽.求這兩只強(qiáng)隊(duì)分在同一組的概率.

8個(gè)籃球隊(duì)中有2個(gè)強(qiáng)隊(duì)，先任意將這8個(gè)隊(duì)分成兩個(gè)組（每組4個(gè)隊(duì)）進(jìn)行比賽，則這兩個(gè)強(qiáng)隊(duì)被分在一個(gè)組內(nèi)的概率是 ．