（iv）Find the number of different selections if the three letters include exactly one $M$$M$MM and exactly one A ．
（iv）如果三个字母恰好 $M$$M$MM 包含一个 A ，则找到不同选择的数量。
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（v）Find the number of different selections if the three letters include at least one M．
（v）如果三个字母至少包含一个 M，请查找不同选择的数量。
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5 In a group of students，the numbers of boys and girls studying Art，Music and Drama are given in the following table．Each of these 160 students is studying exactly one of these subjects．
5 在一组学生中，学习艺术、音乐和戏剧的男生和女生人数如下表所示。这 160 名学生中的每一位都在学习其中一门科目。

（i）Find the probability that a randomly chosen student is studying Music．
（i）求随机选择的学生学习音乐的概率。
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（ii）Determine whether the events＇a randomly chosen student is a boy＇and＇a randomly chosen student is studying Music＇are independent，justifying your answer．
（ii）确定“随机选择的学生是男孩”和“随机选择的学生正在学习音乐”这两个事件是否独立，证明您的答案是合理的。
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（iii）Find the probability that a randomly chosen student is not studying Drama，given that the student is a girl．
（iii）求随机选择的学生不学习戏剧的概率，假设该学生是女生。
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