Han Shuo is a sane person, such a person has a flaw, that is, he can never find the feeling of a heartbeat, many people can find their own feeling of a girl's heartbeat, but people like Han Shuo can't find it, so Han Shuo will have feelings for women, but he will never know the feeling of a heartbeat. Pen, fun, pavilion www. biquge。 info

What day is not seen as every other day, the head is full of each other's shadows, etc... These things couldn't be felt by Han Shuo, a person who was a little too sane.

But today, what made Han Shuo crazy was that after seeing Xu Xian, he suddenly had this feeling of heartbeat, which made Han Shuo feel incredible.

Standing in a distant position, looking at Xu Xian's frowning appearance, the more Han Shuo looked at it, the cuter it became, Han Shuo had never felt this way before, it was a very peculiar feeling, which made Han Shuo a little restless and inexplicable.

Slowly walking into Xu Xian, who was looking down and thinking about the question, Han Shuo smelled the unique fragrance on Xu Xian's body, looking at Xu Xian's beautiful collarbone, Han Shuo was a little obscene.

At this time, Xu Xian looked up, and then saw Han Shuo standing beside him, Xu Xian instinctively sat back a little, looked at Han Shuo a little evasively, and said, "Xiao Shuo, why are you standing behind me?" (After chatting with Xu Xian for a while, Han Shuo asked Xu Xian to call himself Xiao Shuo, because of Han Shuo's understanding of sweet potatoes, Xu Xian also liked this boy who seemed to be very knowledgeable, so he didn't refuse to agree to call the other party Xiao Shuo.) ）

"Ahh Hehe!" was a little nervous by Xu Xian's sudden question, after all, Han Shuo stared at someone's collarbone obscenely just now, "That... This...!" After thinking for a while, Han Shuo didn't think of a reason.

Just when Han Shuo noticed that Xu Xian was obviously a little disgusted by his behavior, suddenly, Han Shuo saw Xu Xian's question and said, "Ah... Sister Xiaoxian, I see that you are worried about the topic, and maybe I will solve it, so come and take a look at your topic. ”

"Will you solve it?" Looking at Han Shuo, Xu Xian laughed and said: "Xiao Shuo, this is a sophomore probability theory and statistics topic, I am very poor in mathematics, especially this probability theory and statistics, I always feel very difficult to learn, so I want to work hard to learn a little more outside of class, but no one teaches me, I still can't understand it." ”

What Xu Xian didn't expect was that he originally thought that Han Shuo, who was only 20 years old, would be a freshman at most if he went to college, and he knew that the topics of probability theory and statistics in his hands at this time could not be learned until the second semester of his sophomore year, so Xu Xian felt a little funny when he heard Han Shuo say that he might be able to solve it, and he also didn't believe the other party.

But what surprised Xu Xian even more was that Han Shuo looked directly at his question, and then read it out slowly: "There are 10 lottery tickets, of which 8 are 2,000 yuan and 2 are 500 yuan. ”

When he finished reading, Han Shuo's eyes narrowed slightly, this was what Han Shuo looked like when he was thinking, and Xu Xian thought that the other party was stumped, so he smiled and said to Han Shuo: "How about it, Xiao Shuo, it's still difficult, it's okay, this is something that you will learn in your sophomore year, in fact, it's normal that you won't." ”

However, just as Xu Xian was busy comforting Han Shuo, at this time, Han Shuo smiled and said, "No, Sister Xiaoxian, this question is very simple."

Let me tell you the answer, this is mainly based on the actual situation.Use hypergeometric distribution (because it is not put back).The following is represented by c(m,n).The combination is represented by c(m,n).Then take three lottery tickets,The probability of getting 5 yuan is mThe probability is p(m)=c(m,2)c(3-m,8)/c(3,10)m, the value is 0,1,2.

Thus, there are p(0)=c(0,2)c(3,8)/c(3,10)=56/120p(1)=c(1,2)c(2,8)/c(3,10)=56/120p(2)=c(2,2)c(1,8)/c(3,10)=8/120, these three cases have summarized all the possibilities, that is, the bonus in the first case is 3*2=6, the second is 1*5+2*2=9, and the third is 2*5+1*2=12, so that the mathematical expectation is e=6*p(0)+9*p(1)+12*p(2)=7.8

The result from the above argument is 7.8, so the mathematical expectation of this person's prize amount is 7.8!

After Han Shuo finished speaking, Xu Xian was completely shocked by Han Shuo, she really never thought that Han Shuo would actually solve the problem that he couldn't figure out in an instant, Xu Xian, who originally didn't believe Han Shuo, was shocked to see Han Shuo at this time.

You must know that Xu Xian is very eager for knowledge, and he has a lot of respect for people with knowledge, at this time, looking at Han Shuo, Xu Xian said with a little respect: "Xiao Shuo, how are you so good? If you can, can you teach me?"

"Of course you can! It's my greatest honor to be able to teach Sister Xiaoxian!" After speaking, Han Shuo sat down next to Xu Xian, but Xu Xian did not dodge this time, on the contrary, in order to be better taught by Han Shuo, he sat with Han Shuo instead, almost leaning against his body.

Han Shuo was also very bad, in the name of this teaching, his right hand slightly hugged Xu Xian's small waist, because it was too close, Xu Xian's hair suddenly fell next to Han Shuo's nose, and then Han Shuo sniffed hard, the beauty was fragrant, refreshing.

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“ohmygod！”

At the door of the practice room of Girls' Generation, after the girls came back from buying something to eat at noon, and just as everyone was about to push the door in, Sunny Lee Soon-gyu, who was the first to stand at the door, looked at a scene in the practice room and screamed in horror.

"Let's go... Go in, little sun?" The girls behind Li Shungui had a lot of opinions about Li Shungui stopping outside and not going in, so they were all urging Li Shungui to enter the practice room.

But Lee Soon-gyu didn't go in, but said to the girls behind him with a look of amazement: "Ah... Don't rush, something is wrong, take a look inside, Xiaoxian is actually sitting tightly with a man, and the man seems to be still hugging Xiaoxian's waist!"

Li Shungui's words made all the girls collectively frightened, and then immediately rushed to the mirror in front of the door, desperately squeezing to look inside.

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