I hope that the middle school will let the eighth grade class (1) recommend a classmate to be the school broadcaster, and Xiaoming, Xiaohua and Xiaoying are all vying to go. Later, everyone came up with two kinds.
The first scheme is reasonable, no matter who draws first, the winning probability is13;
The second scheme is unreasonable and positive; Positive and negative; Anti, anti; There are four situations. The probability of two heads up, two tails up and one head up is 14, 14, 12, which is unfair.