题干

下面是两个可以自由转动的转盘,每个转盘被分成面积相等的几个扇形,并分别标记了数字1,2,3和1,2,3,4.小明和小亮利用这两个转盘做游戏.规则如下:同时转动两个转盘,指针停止后,将指针所指区域的数字相加(若指针停在分界线上,则重新转动转盘),如果和为奇数,则小明获胜,如果和是偶数,则小亮获胜,请你确定游戏规则是否公平,并说明理由.

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答案(点此获取答案解析)

解:根据题意画树状图如下:

∵共有12种等可能的结果,和为奇数的有6种情况,和为偶数有6种情况,

∴P(小明获胜):

同类题1

完形填空,阅读下面的短文, 从短文后所给的四个选项中, 选出可填入空白处的最佳选项。   

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