The absolute value of 1 Yes ()
A.- 3rd century BC.
2. The following calculation is correct ()
A.B. C. D。
3. Of the following statements about the monomial, the correct one is ()
A. The coefficient is 1, the degree is 2 B, the coefficient is, and the degree is 2.
C. the coefficient is, the degree is 3 d, the coefficient is, and the degree is 3.
4. The following statement is wrong ()
A. Cuboids and cubes are prisms. B. The sides of a triangular prism are triangles.
C a regular hexagonal prism has six sides, and the sides are rectangular. D all three views of the sphere are graphs of the same size.
In a shopping mall, two shirts with different purchase prices were sold to 80 yuan, with a profit of 60% and a loss of 20%. Merchant () in this transaction.
A. earned 10 yuan B. earned 8 yuan C. earned 32 yuan without loss.
6. The following figure is a cubic surface expansion diagram, which is ()
7. As shown in the figure, B is the midpoint of line segment AD and C is the point on BD, so the following conclusion is wrong ().
A.BC=AB-C D B.BC= (AD-CD)
C.BC= AD-CD D.BC=AC-BD
8. A city has 70,000 candidates taking the senior high school entrance examination this year. In order to know the math scores of these 70,000 candidates, we selected them.
This paper makes a statistical analysis of the mathematics scores of 1000 candidates. The correct statement is ().
A.2B.3C.4D.0
This survey adopts the method of sampling survey, and the total number of candidates is 270,000.
③ 1000 candidates are a whole sample ④ Each candidate's math scores are individual.
2. Fill in patiently (3 points for each question, * * * 24 points)
9. At present, Shanghai Tower, the tallest building under planning in China, has a total investment of about 148 billion yuan. 65,438+04,800,000 yuan is expressed by scientific notation.
10. If x=2 is the solution of the equation mx- 1=2, then m=.
1 1. As shown in the figure, there are three channels A, B and C from point A to the nearest point B.
The channel is because.
12. Girls account for 52% of the total number of students in a school, 80% more than boys. If the number of students in this school is X, then an equation can be drawn.
13. If the value of the algebraic expression 3x-8y is 20 10, then the value of the algebraic expression 2(x+6y)-8(x-y)-4-4y is.
On 14. 19: 45, the angle between the hour hand and the minute hand of the clock is.
15. If, contrary to each other and reciprocal to each other, then _ _ _ _.
16. Which of the following events are inevitable, impossible and possible?
(1) The two points in the dice are;
(2) The product of two numbers with the same sign is negative;
(3) Two numbers with opposite numbers add up to zero.
Third, do it seriously (17, 18, 10 8)
17. Calculation: (4 points for each small question, ***8 points)
( 1) (2) (-2)2+(-2)(- )+ (-24)
18. Simplify first, then evaluate (5 points for each small question, *** 10)
(1), where a=-.
(2) 2x-y-(2y2-x2)-5x+y+(x2+2y2)，x=- 1，y= 1。
Four, calm and careful consideration (19 10, 20 10)
19. Solve the equation: (5 points for each small question, *** 10)
( 1) (2) - 1=
20.( 10) Complete the following questions as required:
(1) There is a small cube in the graph;
Please draw its front view, left view and top view respectively below.
V (each of the v(22 questions is 2 1, 10)
2 1.( 10) Some students from Class 1, Grade 7 participated in the National Hope Cup Mathematics Invitational Tournament and achieved excellent results. They instructed the teacher to count the scores of all the students participating in the competition (the score is an integer, and the full score is 150), and drew a statistical chart as shown in the following figure (note: the highest score is not included in each group).
Please answer:
(1) How many students are there in this class?
(2) If the students whose scores are not less than 1 10 win the prize, what is the winning rate of this class?
(3) How many students passed the competition? (Pass if the score is not less than 60% of the total score)
22.( 10) The following is a problem solved by Xiao careless:
Topic: If BOA=70 and BOC=25 on the same plane, find the degree of AOC.
Solution: You can draw a picture according to the meaning of the problem.
* AOC = BOA-BOC
=70-25
=45
AOC=45
If you were a teacher, would you get full marks for carelessness?
If yes, explain the reasons. If not, please point out the careless mistakes and give your correct solutions.
6. Use your head and make persistent efforts (23 questions and 24 questions each 10)
23.( 10) There is a treasure-digging game, in which a treasure is randomly hidden in the circular area below (the circular area is divided into eight equal parts), as shown in figure 1.
(1) If you were looking for treasure, which region would you choose (region1; Region 2; Area 3)? Why? Are you sure you can find treasure around here?
(2) Where are the two areas of hidden treasure?
(3) What happens if the area where the treasure is buried is as shown in Figure 2 (each square in the figure is exactly the same) and (1)(2)?
24.( 10 minute) The distance between A and B is 64 kilometers. A starts from A at a speed of 14 km, and B starts from B at a speed of 18 km.
(1) If two people leave at the same time, how many hours will it take to meet?
(2) If A is in front and B is behind, and both of them walk in the same direction at the same time, how many hours will B exceed A 10 km?
Seven. Use knowledge to solve problems.
25.( 14) If a green vegetable is produced in a certain place and sold directly in the market, the profit per ton is 1000 yuan; After rough machining, the profit per ton can reach 4500 yuan; After fine processing and sales, the profit per ton rose to 7500 yuan. A local agricultural and industrial company harvested 140 tons of this vegetable. The processing capacity of this company is: if vegetables are roughly processed, they can process 16 tons per day; If fine processing is carried out, 6 tons can be processed every day, but the two processing methods cannot be carried out at the same time. Due to the season and other conditions, the company must sell or process all these vegetables within 15 days, so the company has formulated three feasible schemes.
Scheme 1: Roughing all vegetables;
Option 2: Refine vegetables as much as possible, and sell vegetables that are not processed in time directly in the market;
Scheme 3: Sort out some vegetables, roughly process the remaining vegetables, and sort them in 15 days.
Which scheme do you think is the most profitable? Why?
8. Full of confidence, success is in sight.
26. (5 points for each small question * *10)
(1) Look at the picture below and answer the following questions:
(1) If 1 ray oc is drawn inside the AOB, different angles will appear in the figure;
(2) If two rays OC and OD are drawn inside AOB, different angles will appear in the picture;
(3) Draw three rays OC, OD and OE inside the AOB, which have a different angle;
(4) Draw 10 rays OC, OD and OE inside AOB, with different angles in the drawing;
(5) Draw n rays OC, OD, OE inside the AOB, which have a different angle.
(2) Observe the following equation:
rule
And please use an equation containing (a positive integer) to express the law of thought.
Yes: _ _ _ _ _ _ _ _ _ _ _ _ _ _.
Reference answer:
Title 1 2 3 4 5 6 7 8
Answer C D D B A C B A
9.1.48 1010 yuan10. 1 1.b, the line segment between two points is the shortest.
17.( 1) solution: the original formula = (-48)+(-48)-(-48)-2 points.
=-8+(-)-(- 12)+(-4) - .
=-8- + 12-4
= - .
(2) Solution: The original formula = 4+(-2) (-)+(- 16)-2 points.
= 4+3- 1 - .
= 6 - .
18.( 1) solution: 5a2-3a+6-4a2+7a,
=5a2-4a2+(-3a+7a)+6
= A2+4A+6 -。
When a=-,
The original formula = (-) 2+4 (-)+6-4 points.
= -2+6
= - .
(2) Solution: 2x-y-(2y2 -x2)-5x+y+(x2+2y2),
=2x-y-2y2+x2-5x+y+x2+2y2
=(2x-5x)+(-y+y)+(-2 y2+2 y2)+(x2+x2)
=-3x+2x2-2 points.
When x =- 1 and y = 1,
The original formula =-3 (- 1)+2 (- 1) 2-.
=3+2
= 5-5 points.
(2) Solution: 3 (3x-1)-12 = 2 (5x-7) after the denominator is removed.
Without brackets: 9x-3-12 =10x-143 points.
Goods transferred: 9x-10x =-14+3+124 points.
Merge similar projects: -x= 1
Divide both sides of the equation by-1 to get: x =- 1.5 points.
20.6 blocks -2 points.
Front view -5 points left view -8 points top view-10 point.
21.(1) 3+6+8+2+1= 20 people
So 20 students in this class took part in the competition. -Three points.
(2)(2+ 1)20 100%= 15%
So the winning rate of students in this class is 15%-6 points.
(3) 8+2+1=1person
So 1 1 passed the exam.
22. Solution: A little carelessness won't get full marks. -Two points.
Small careless consideration is not comprehensive, only know that the Bank of China is in Bao Er.
Another situation is that BOC is outside BOA. -Five points.
The solution is as follows: according to the meaning of the question, you can draw a picture (as shown in the figure),-6 points.
∫AOC = BOA+BOC
=70+25
=95
AOC = 95-8 points.
Combining the above two situations, AOC=45 or 95. -10.
23. Solution: A: (1) will choose Zone 3; The possibility of 1 area and area 2 is that the possibility of area 3 is that the possibility of hiding in area 3 is high; Treasure may not be found in this area, because the possibility of Zone 3 is not 1. (Just name the possibility of who, and give points as appropriate)-6 points.
24. Solution: (1) If two people start at the same time and move in opposite directions,
If it takes x hours for two people to meet, according to the meaning of the question, the score is:-1.
14x+ 18x = 64-3 points.
Solution: x = 2-4 points.
So, if two people leave at the same time, it will take two hours for them to meet. -Five points.
(2) If A is in front and B is behind, both of them will go in the same direction at the same time.
Suppose that after y hours, b exceeds A 10 km.
18y-14y = 64+10-8 points.
Solution: y = 18.5-9 points.
Therefore, if A comes first, B comes last, and both of them walk in the same direction at the same time, B will exceed A 18.5 hours.
-10.
25. Solution: Option 1: Profit (RMB),-3 points.
Option 2: 15 days can finish (tons), indicating that there are still 50 tons to be sold directly in the market.
So you can make a profit (RMB) -7 points.
Scheme 3: Tons of vegetables can be finely processed and tons of vegetables can be roughly processed.
According to the meaning of the question,-10 points.
Score:-12.
Therefore, the profit (RMB)-13 points.
To sum up, scheme 3 is the most profitable. -14 points.
26. 1.( 1)3; (2)6; (3) 10; (4) 1+2+3++ 10+ 1 1=66; -Four points.
(5) 1+2+3 ++ n+(n+ 1)=； -Seven points.
2.8-8-8 points.
1+3+5+7 ++( 2n- 1)= N2- 10。