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数学 高校生

マルで囲ったとこがどうしてこうおけるのかわかりません😭教えてください!!

EX 428 基本 例題 59 条件付き確率の計算 (2) ... 場合の数利用 00000 3個のさいころを同時に投げ, 出た目の最大値をX, 最小値を Yとし、その X-YをZとする。 (1) Z=4 となる確率を求めよ。 (2) Z=4 という条件のもとで,X = 5 となる条件付き確率を求めよ。 / P.425 基本 指針 (1) 1≦X66 から, Z=4となるのは, (X, Y) = (5,1) (62) のときで (2) Z4となる事象をA, X=5 となる事象をBとすると, 求める確率は 条件付き ある。この2つの場合に分けて, Z4 となる目の出方を数え上げる。 確率 P(B)である。 (1)n(A),n(A∩B)を求めているから, 全体をAとしたときのA∩Bの割合 n(A∩B) PA(B)= n(A) を利用して計算するとよい。 (1) Z4となるのは, (X, Y) =(5, 1), 6, 2 のとき 解答 [1] (X, Y)=(51) のとき このような3個のさいころの目の組を, 目の大きい方 から順にあげると, 次のようになる。 [2] (X, Y)=(62) のとき [1] と同様にして,目の組を調べると Z=X-Y=4から X=Y+4 X≦6 であるためには Y = 1 または Y = 2 (5, 5, 1), (5, 4, 1), (5,3, 1), (5,2,1), (5,1,1) 3! 3! [1] の目の出方は + 3×3! + =24(通り) 21 2! (6,6,2), (6,5,2), (6,4,2), (6,3,2), (6,2,2) [2] の目の出方は 3! 3! 組 (5.5.1)と組 (5,1,1)については、 同じものを含む順列を利 用。(同じものがない1 個の数が入る場所を選ぶ と考えて, C, としても よい。) + 3×3! + -=24(通り) 2! 2! 以上から,Z4となる目の出方は 24+24=48 (通り) 他の3組については順列 を利用。 よって, 求める確率は 48 2 63 9 基本 例題 60 「10本のくじの中に (1) 初めにaが1 (ア) a, b ともに (2) 初めが1本 る確率を求めよ 指針 解答 順列の考え 「a, b の順に 果がb の結 算する。 (1) a (ア) 求め (イ) b に分け 当たることを (1)a が当た Bとする。 7 (ア) P(A)= P (イ) b が当 があり, 求める確 P (2) a, b {ax, a C に排反であ と、求める確率は (2)Z4となる事象を A, X=5 となる事象をBとするP. (B) P(B)=n(A∩B)_24 1 P(A∩B)_n(A∩B) n(A) 48 2 P(A) n(A) POINT 条件付き確率はP(B)=P(A∩B) かP(B)= P(A) n(ANB) で計算 n(A) 練習 2個のさいころを同時に1回投げる。 出る目の和を5で割った余りをX.出る目の ③ 59積を5で割った余りをYとするとき、次の確率を求めよ。 (1) X = 2 である条件のもとで Y=2 である確率 (2) Y = 2 である条件のもとで X=2である確率 p.436 EX42.45 検討上の例題の (1) と等しい。 一 練習 8本のくじの ② 60 めに aが1本 (1) 初めに (2) a, bet

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英語 中学生

問3 ェ 問5 イ 問6 ウエ なぜそうなるのかの解説お願いします

次の英文は,日本にホームステイしているエミリー(Emily) のことを書いたものです。これを読んで問いに答えなさい。 Emily is a high school student from the U.S. She is interested in Japan very much. She came to Japan and has stayed at Taro's house for one month. She is enjoying her stay in Sapporo. (1) One day, she went to a movie with Taro. The movie was really nice, so it made them excited. After that, they took a *subway to go back to their home. Emily was telling him what she thought about the quiet. He said, "Please talk in a small voice. movie_in_a *loud voice on the subway, so Taro In Japan, we are usually quiet on the subway." She was surprised to hear that, so she said to Taro, "Sorry, but I don't know why we have to be so quiet. In the U.S., we can talk with each other on the subway. Sometimes some people dance and sing a song." This time Taro was surprised to hear that. ① The next day, Emily was talking with Taro's father. She said, “Today I saw something *strange when I was on the subway. There were so many people and most of them could not sit down. Only one *seat was *empty, but *no one tried to sit there." Taro's father answered, “Did you see a sign near the seat? That seat is only for people who need some help like *elderly people or *pregnant women, or people with special *needs. *Even if there are no elderly people standing on the subway, other people won't sit there. The *priority seats are on the buses and trains in many towns in Japan, but the seats like this only in Sapporo." Emily thinks everyone should give a seat to elderly people or pregnant women. By doing so, they won't need special seats on the subway. Emily will stay in Sapporo for more two months and そうすることで (E) subway T loud... 大きな strange... おかしな, 奇妙な empty 空いている no one ~ ・だれも~しない seat... elderly ・・・ 高齢の even if ~・・・ たとえ~でも

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英語 高校生

(4)について This is why にしてしまいました。  This is becauseというようなThis is whyの表現ではだめな理由を教えてください

(60分) Ⅰ 次の英文を読んで、下の設問 (1)~ (11) の語には注が付いています。 に答えなさい。 なお、 Food is fuel. When your body needs energy, you eat. When it doesn't you don't. It should be so simple when you think about it, but that's exactly the problem: us big smart humans can and do think about it, (, introduces all manner of problems and neuroses*. Have you noticed how you always have "room for dessert"? You might have just eaten the best part of a cow, or enough cheesy pasta to sink a gondola, but you can manage that fudge brownie or sundae. Why? How? If your stomach is full, how ice cream triple-scoop b) eating more even physically possible? It's largely because your brain makes an executive decision and decides that, no, you still have room. The sweetness of desserts is a palpable* reward (7)that the brain recognizes and wants so it overrules the stomach. C Exactly {c case is ③ is 4 the this why) uncertain. It may be that humans need quite a complex diet in order to remain in tip-top* condition, so rather than just relying on our basic metabolic systems to eat whatever is available, the brain steps in and tries to regulate our diet better. And this would be fine if that was all the brain does. But it doesn't. So it isn't. Learned associations are incredibly powerful when it comes ( d ) eating. You may be a big fan of something like, say, cake. You can be eating cake for years without any bother, then one day you eat some cake that makes you vomit. Could be some of the cream in it has gone sour; it might contain an ingredient you're allergic to; or (and here's the annoying one) it could be that something else entirely made you throw up shortly after eating cake. out of The disgust eating poiso g And it consider th The brain than food, it doesn't worryingl needlessl one of li shovelin the brai (注) (1) (2

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