LFM Stats And Pure

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gaokao 2015 Q17 Combinatorial Counting (Non-Probability) View
17. (This question is worth 12 points)
A minibus has 5 seats numbered $1,2,3,4,5$. Passengers $P _ { 1 } , P _ { 2 } , P _ { 3 } , P _ { 4 } , P _ { 5 }$ have assigned seat numbers $1,2,3,4,5$ respectively. They board in order of increasing seat numbers. Passenger $P _ { 1 }$ did not sit in seat 1 due to health reasons. The driver then requires the remaining passengers to be seated according to the following rule: if their own seat is empty, they must sit in their own seat; if their own seat is occupied, they can choose any of the remaining empty seats. (1) If passenger $P _ { 1 }$ sits in seat 3 and other passengers are seated according to the rule, there are 4 possible seating arrangements. The table below shows two of them. Please fill in the remaining two arrangements (enter the seat numbers where passengers sit in the blank cells);
(2) If passenger
Passenger$P _ { 1 }$$P _ { 2 }$$P _ { 3 }$$P _ { 4 }$$P _ { 5 }$
\multirow{3}{*}{Seat Number}32145
32451

$P _ { 1 }$ sits in seat 2, and other passengers are seated according to the rule, find the probability that passenger $P _ { 5 }$ sits in seat 5.
gaokao 2017 Q1 Set Operations View
Let the set $A = \{1,2,3\}$, $B = \{2,3,4\}$, then $A \cup B =$
A. $\{1,2,3,4\}$
B. $\{1,2,3\}$
C. $\{2,3,4\}$
D. $\{1,1,4\}$
gaokao 2018 Q1 5 marks Set Operations View
Given sets $A = \{ 0,2 \}$ and $B = \{ - 2 , - 1,0,1,2 \}$, then $A \cap B =$
A. $\{ 0,2 \}$
B. $\{ 1,2 \}$
C. $\{ 0 \}$
D. $\{ - 2 , - 1,0,1,2 \}$
gaokao 2018 Q1 5 marks Set Operations View
Given sets $A = \{ x \mid x - 1 \geqslant 0 \} , B = \{ 0,1,2 \}$, then $A \cap B =$
A. $\{ 0 \}$
B. $\{ 1 \}$
C. $\{ 1,2 \}$
D. $\{ 0,1,2 \}$
gaokao 2018 Q2 5 marks Set Operations View
Given sets $A = \{ 1,3,5,7 \} , B = \{ 2,3,4,5 \}$, then $A \cap B =$
A. $\{ 3 \}$
B. $\{ 5 \}$
C. $\{ 3,5 \}$
D. $\{ 1,2,3,4,5,7 \}$
gaokao 2018 Q2 5 marks Combinatorial Counting (Non-Probability) View
Given set $A = \left\{ ( x , y ) \left| x ^ { 2 } + y ^ { 2 } \leqslant 3 , x \in \mathbf { Z } , y \in \mathbf { Z } \right. \right\}$, the number of elements in $A$ is
A. 9
B. 8
C. 5
D. 4
gaokao 2018 Q8 5 marks Finite Equally-Likely Probability Computation View
Chinese mathematician Chen Jingrun achieved world-leading results in research on Goldbach's conjecture. Goldbach's conjecture states that ``every even number greater than 2 can be expressed as the sum of two prime numbers'', such as $30 = 7 + 23$. Among prime numbers not exceeding 30, if two different numbers are randomly selected, the probability that their sum equals 30 is
A. $\frac { 1 } { 12 }$
B. $\frac { 1 } { 14 }$
C. $\frac { 1 } { 15 }$
D. $\frac { 1 } { 18 }$
gaokao 2019 Q3 Set Operations View
3. After the examination ends, submit both this test paper and the answer sheet. Section I: Multiple Choice Questions: This section has 12 questions, each worth 5 points, for a total of 60 points. For each question, only one of the four options is correct.
1. Given sets $M = \{ x \mid - 4 < x < 2 \} , N = \left\{ x \mid x ^ { 2 } - x - 6 < 0 \right\}$ , then $M \cap N =$
A. $\{ x \mid - 4 < x < 3 \}$
B. $\{ x \mid - 4 < x < - 2 \}$
C. $\{ x \mid - 2 < x < 2 \}$
D. $\{ x \mid 2 < x < 3 \}$
2. Let complex number $z$ satisfy $| z - \mathrm { i } | = 1$ , and the point corresponding to $z$ in the complex plane is $( x , y )$ , then
A. $( x + 1 ) ^ { 2 } + y ^ { 2 } = 1$
B. $( x - 1 ) ^ { 2 } + y ^ { 2 } = 1$
C. $x ^ { 2 } + ( y - 1 ) ^ { 2 } = 1$
D. $x ^ { 2 } + ( y + 1 ) ^ { 2 } = 1$
3. Given $a = \log _ { 2 } 0.2 , b = 2 ^ { 0.2 } , c = 0.2 ^ { 0.3 }$ , then
A. $a < b < c$
B. $a < c < b$
C. $c < a < b$
D. $b < c < a$
gaokao 2019 Q4 Set Operations View
4. According to historical records, the ``Hundred Family Names'' was written in the early Northern Song Dynasty. Table 1 records the top 24 surnames from the beginning of the ``Hundred Family Names'':
\begin{table}[h]
Table 1

\end{table}
Table 2 records the top 25 most populous surnames in China in 2018:
\begin{table}[h]
Table 2
1: Li2: Wang3: Zhang4: Liu5: Chen
6: Yang7: Zhao8: Huang9: Zhou10: Wu
11: Xu12: Sun13: Hu14: Zhu15: Gao
16: Lin17: He18: Guo19: Ma20: Luo

\end{table}
21: Liang22: Song23: Zheng24: Xie25: Han

If one surname is randomly selected from the top 24 surnames in the ``Hundred Family Names'', the probability that this surname is among the top 24 most populous surnames in China in 2018 is
A. $\frac { 5 } { 12 }$ B. $\frac { 11 } { 24 }$ C. $\frac { 13 } { 24 }$ D. $\frac { 1 } { 2 }$
gaokao 2019 Q5 Set Operations View
5. After the examination ends, submit both this test paper and the answer sheet together. I. Multiple Choice Questions: This section has 12 questions, each worth 5 points, for a total of 60 points. For each question, only one of the four options is correct.
1. Given sets $M = \{ x \mid - 4 < x < 2 \} , N = \left\{ x \mid x ^ { 2 } - x - 6 < 0 \right\}$, then $M \cap N =$
A. $\{ x \mid - 4 < x < 3 \}$
B. $\{ x \mid - 4 < x < - 2 \}$
C. $\{ x \mid - 2 < x < 2 \}$
D. $\{ x \mid 2 < x < 3 \}$
2. Let complex number $z$ satisfy $| z - \mathrm { i } | = 1$, and the point corresponding to $z$ in the complex plane is $( x , y )$, then
A. $( x + 1 ) ^ { 2 } + y ^ { 2 } = 1$
B. $( x - 1 ) ^ { 2 } + y ^ { 2 } = 1$
C. $x ^ { 2 } + ( y - 1 ) ^ { 2 } = 1$
D. $x ^ { 2 } + ( y + 1 ) ^ { 2 } = 1$
3. Given $a = \log _ { 2 } 0.2 , b = 2 ^ { 0.2 } , c = 0.2 ^ { 0.3 }$, then
A. $a < b < c$
B. $a < c < b$
C. $c < a < b$
D. $b < c < a$
4. In ancient Greece, people believed that the most beautiful human body has the ratio of the length from the top of the head to the navel to the length from the navel to the sole of the foot equal to $\frac { \sqrt { 5 } - 1 } { 2 } \left( \frac { \sqrt { 5 } - 1 } { 2 } \approx 0.618 \right.$, called the golden ratio), and the famous ``Venus de Milo'' exemplifies this. Furthermore, the ratio of the length from the top of the head to the throat to the length from the throat to the navel is also $\frac { \sqrt { 5 } - 1 } { 2 }$. If a person satisfies both golden ratio proportions, with a shoulder width of 105 cm and the length from the top of the head to the chin of 26 cm, then their height could be [Figure]
A. 165 cm
B. 175 cm
C. 185 cm
D. 190 cm
5. The graph of the function $f ( x ) = \frac { \sin x + x } { \cos x + x ^ { 2 } }$ on $[ - \pi , \pi ]$ is approximately
A. [Figure]
B. [Figure]
C. [Figure]
D. [Figure]
gaokao 2021 Q1 Set Operations View
1. Let $M = \{ 1,3,5,7,9 \} , N = \{ x \mid 2 x > 7 \}$, then $M \cap N = ( )$
A. $\{ 7,9 \}$
B. $\{ 5,7,9 \}$
C. $\{ 3,5,7,9 \}$
D. $\{ 1,3,5,7,9 \}$
gaokao 2021 Q1 Set Operations View
1. Let sets $M = \{ x \mid 0 < x < 4 \}, N = \left\{ x \left\lvert \, \frac { 1 } { 3 } \leq x \leq 5 \right. \right\}$, then $M \cap N =$
A. $\left\{ x \left\lvert \, 0 < x \leq \frac { 1 } { 3 } \right. \right\}$
B. $\left\{ x \left\lvert \, \frac { 1 } { 3 } \leq x < 4 \right. \right\}$
C. $\{ x \mid 4 \leq x < 5 \}$
D. $\{ x \mid 0 < x \leq 5 \}$
gaokao 2021 Q2 Set Operations View
2. Let $U = \{ 1,2,3,4,5,6 \} , A = \{ 1,3,6 \} , B = \{ 2,3,4 \}$. Then $A \cap \left( \complement_U B \right) =$
A. $\{ 3 \}$
B. $\{ 1,6 \}$
C. $\{ 5,6 \}$
D. $\{ 1,3 \}$
【Answer】B 【Solution】 【Analysis】Use the definitions of intersection and complement to find $A \cap \left( \complement_U B \right)$. 【Detailed Solution】From the given conditions, $\complement_U B = \{ 1,5,6 \}$, so $A \cap \left( \complement_U B \right) = \{ 1,6 \}$, Therefore, the answer is: B.
gaokao 2022 Q1 5 marks Set Operations View
Let set $A = \{ - 2 , - 1,0,1,2 \} , B = \left\{ x \left\lvert \, 0 \leq x < \frac { 5 } { 2 } \right. \right\}$ , then $A \cap B =$( )
A. $\{ 0,1,2 \}$
B. $\{ - 2 , - 1,0 \}$
C. $\{ 0,1 \}$
D. $\{ 1,2 \}$
gaokao 2022 Q1 5 marks Set Operations View
Set $M = \{ 2,4,6,8,10 \} , N = \{ x \mid - 1 < x < 6 \}$ , then $M \cap N =$
A. $\{ 2,4 \}$
B. $\{ 2,4,6 \}$
C. $\{ 2,4,6,8 \}$
D. $\{ 2,4,6,8,10 \}$
gaokao 2022 Q1 5 marks Set Operations View
Let the universal set $U = \{ 1,2,3,4,5 \}$, and set $M$ satisfies $C_U M = \{ 1,3 \}$. Then
A. $2 \in M$
B. $3 \in M$
C. $4 \notin M$
D. $5 \in M$
gaokao 2022 Q2 5 marks Set Operations View
Let $U = \{ 1,2,3,4,5,6 \} , A = \{ 1,3,6 \} , B = \{ 2,3,4 \}$. Then $A \cap \left( \complement_U B \right) =$
A. $\{ 3 \}$
B. $\{ 1,6 \}$
C. $\{ 5,6 \}$
D. $\{ 1,3 \}$
gaokao 2022 Q5 Probability Involving Algebraic or Number-Theoretic Conditions View
5. From 7 integers from 2 to 8, two different numbers are randomly selected. The probability that these two numbers are coprime is
A. $\frac { 1 } { 6 }$
B. $\frac { 1 } { 3 }$
C. $\frac { 1 } { 2 }$
D. $\frac { 2 } { 3 }$
gaokao 2023 Q1 5 marks Set Operations View
Let $A = \{ x \mid x = 3k + 1 , k \in Z \} , B = \{ x \mid x = 3k + 2 , k \in Z \} , U$ be the set of integers, then $C_{U}(A \bigcap B) =$
A. $\{ x \mid x = 3k , k \in Z \}$
B. $\{ x \mid x = 3k - 1 , k \in Z \}$
C. $\{ x \mid x = 3k - 1 , k \in \mathrm{Z} \}$
D. $\varnothing$
gaokao 2023 Q2 Set Operations View
Let the universal set $U = \mathbb{R}$, set $M = \{ x \mid x < 1 \}$, $N = \{ x \mid - 1 < x < 2 \}$, then $\{ x \mid x \geqslant 2 \} =$
A. $C _ { U } ( M \cup N )$
B. $N \cup C _ { U } M$
C. $C _ { U } ( M \cap N )$
D. $M \cup C _ { U } N$
gaokao 2023 Q2 5 marks Set Operations View
Let $A=\{0,-a\}$, $B=\{1,a-2,2a-2\}$. If $A\subseteq B$, then $a=$
A. 2
B. 1
C. $\frac{2}{3}$
gaokao 2024 Q1 4 marks Set Operations View
Given sets $M = \{ x \mid - 4 < x \leq 1 \} , N = \{ x \mid - 1 < x < 3 \}$, then $M \cup N =$ \_\_\_\_
gaokao 2024 Q1 5 marks Set Operations View
Given sets $A = \left\{ x \mid - 5 < x ^ { 3 } < 5 \right\} , B = \{ - 3 , - 1,0,2,3 \}$ , then $A \cap B =$
A. $\{ - 1,0 \}$
B. $\{ 2,3 \}$
C. $\{ - 3 , - 1,0 \}$
D. $\{ - 1,0,2 \}$
gaokao 2025 Q2 5 marks Set Operations View
Let the universal set $U = \{x \mid x \text{ is a positive integer less than } 9\}$, and set $A = \{1,3,5\}$. Then the number of elements in $\complement_U A$ is
A. $2$
B. $3$
C. $5$
D. $8$
gaokao 2025 Q2 5 marks Set Operations View
Let the universal set $U = \{1,2,3,4,5,6,7,8\}$, and set $A = \{1,3,5\}$. The number of elements in $C_U A$ is
A. $0$
B. $3$
C. $5$
D. $8$