题库搜索>问题求解PS-13510
From a group of 3 boys and 3 girls, 4 children are to be randomly selected. What is the probability that equal numbers of boys and girls will be selected?
分析A选项
分析B选项
分析C选项
分析D选项
分析E选项
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男女数目相同 C32*C32=9
一共有 C64=15 种可能性
9/15=3/5 选D
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