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数学 高校生

なぜ2の最後って積で確率を求めるのですか?

422 重要 例題 56 図形上の頂点を動く点と確率 0000 円周を6等分する点を時計回りの順に A, B, C, D, E, Fとし, 点Aを出発点 として小石を置く。 さいころを振り, 偶数の目が出たときは2, 奇数の目が出た ときには1だけ小石を時計回りに分点上を進めるゲームを続け、最初にAに ちょうど戻ったときを上がりとする。 (1) ちょうど1周して上がる確率を求めよ。 (2) ちょうど2周して上がる確率を求めよ。 指針 さいころを振ることを繰り返すから, 反復試行である。 (1) 1周して上がる → 偶数の回数m, 奇数の回数nの 方程式を作る。 [北海道] 基本52 重要 例題 さいころを続け 率は100 6 数 指針 (ア) 求め (イ)確 pk+1 かし や CH ..... 1,2をいくつか足して6にする。 F 偶 1周目にAにあってはいけない。 E BAはともに5だけ進むから,同じ確率になる。 D (2) 2周して上がる ...... A → F, F → B, B → A と分ける。 このときA→Fと (c) (1.4)のとき 2m+n=6 (1) ちょうど1周して上がるのに, 偶数の目が回 奇数の目がn と 解答 (m,nは0以上の整数) よって (m, n)=(0, 6), (1, 4), (2, 2), (3, 0) これらの事象は互いに排反であるから, 求める確率は ①②③④⑤ 43 ぐききき 5! [14] (2,2)のとき 2 +oC(1/2)(1/2)+(1/2)^(1/2)+(1/2)=1 64 回出ると (2) ちょうど2周して上がるのは,次の[1]→[2] → [3] の順に進む場合である。 [1] A から F に進む5逾[2] F から B に進む (A には止まらない) [3]BからAに進む進む (1) と同様に考えて, [1] ~ [3] の各場合の確率は ①②③④ [1] 2m+n=5から き この場合の確率は (m, n)=(0, 5), (1, 3), (2, 1) E (1/2)+(1/2)(1/2)+oca(1/2)(1/2)=3/2 [2] 偶数の目が出るときであるから,確率は 2.2 [3] 確率は[1] と同じであり よって, 求める確率は 21 × 32 21 23 12 +C 12 [3] BからAに進むと 21 441 5だけ進む。 これは [1] のAからFに進む (5 け進む)のと同じであり × 32 2048 確率も等しい。 さいこ 答 確率を 答 OES ここ PR- Þ 両 練習動点Pが正五角形ABCDE の頂点 A から出発して正五角形の周上を動くものと © 56 る。Pがある頂点にいるとき, 1秒後にはその頂点に隣接する2頂点のどちらか それぞれ確率 1/12 で移っているものとする。 (1)PがAから出発して3秒後にEにいる確率を求めよ。 練習 5 57 (2)PがAから出発して4秒後にBにいる確率を求めよ。 (3)PがAから出発して9秒後にAにいる確率を求めよ。 [類 産能大

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英語 高校生

付箋で貼った2文がどうしてそのような訳になるのかわかりません。

た次の英文を読み, 設問に答えなさい。 (学習院 法学部 2022年) Society is everything. Many of us go through life thinking we are self-made and self-sufficient. Some may credit (or blame) their families for success or failure in life, but rarely do we think about (1) the bigger forces (that determine our destinies - the country we happen to be born in, the social attitudes common at a particular moment in history, the institutions that govern our economy and politics, and the randomness of just plain luck. These wider factors determine the kind of society in which we live and are the most important determinants of our human experience. 2 Consider an example of a life in which society plays a very (X) role. In 2004 I spent time with a family in the Ecuadorian Amazon*. Antonia, my host, had twelve children, and her oldest daughter was about to give birth to her first grandchild. They lived on the edge of the rainforest with no road, electricity, clean water or sanitation*. There was a school, but a considerable distance away, (Y) the children's attendance was irregular However, Antonia was a community health worker and had access via radio* to a doctor in a nearby town who could provide advice to her and others. Apart from this service (arranged by a charity), she and her husband had to be completely self-reliant gathering food from the forest, educating their children on how to survive in their environment. On the rare occasions when they needed something they could not find or make themselves (like a cooking pot), they searched for bits of gold in the Amazon, which they could exchange for goods in a market at the end of a long journey by boat. 3 This may seem like a very extreme and distant example, but it serves to remind us how accustomed we are to the things that living collectively gives us infrastructure, education and health care, laws that enable markets in which we can earn incomes and access goods and services. Antonia and her daughter promised to name the baby (they were Minouche, (2) which was a great honour. I often wonder what kind of life that other Minouche will be having as a result of being born in a very different society. V+ re expecting The way a society is structured has profound consequences for the lives of those living in it and the kinds of opportunity they face. It determines not just their material conditions but also their well-being, relationships and life The structure of society is determined by institutions such astical and legal systems, the economy, the way in which family and community life are organized. All societies choose to have some things left to individuals and others determined collectively. The rules governing how ? those collective institutions operate form what might be called the social contract, which 1 believe is the most important determinant of the kinds of lives we lead. Because it is so important and because most people cannot easily leave their societies, the social contract requires (Z) of the majority and necessary changes ás circumstances change. VF vf ⑤We are living at a time when, in many societies. people feel disappointed by the social contract and (3) the life it offers them. This is despite the huge gains in material progress the world has seen over the last 50 years. Surveys Social contract people

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