1 and decimal 2.995 are accurate to 0.0 1, and the correct answer is ().
A 2.99 B 3 C 3.0 D 3.00
2. Please select your step size () from the following data.
50 mm B 50 cm C 50 decimeter D 50 meter
When Xiaoming comes home at 3 pm. End with a neon head and draw with a stupid sheath. ? /DIV & gt；
A acute angle b right angle c obtuse angle d cannot be determined.
4. The line segment of 1cm on the map indicates the actual distance of 5km, and the scale of this map is ().
A 1:5000 B 1:50000
C 1:500000 D 1:500000
5. There are Y students in Grade One (1), among whom 45% are girls, so the number of boys is ().
A 45%y B ( 1-45%)y
C y/45% D y/( 1-45%)
6. It is known that four empty bottles of mineral water can be exchanged for one bottle of mineral water, and there are 13 empty bottles of mineral water. If you don't pay, you can drink mineral water at most ().
A 3 bottles, B 4 bottles, C 5 bottles and D 6 bottles.
7. Mom asked Xiaoming to boil water and make tea for the guests. It takes 1 min to boil the kettle, 1 min to boil the water, 1 min to wash the teapot,1min to wash the teacups, and 2 min to put the tea. How many minutes can Xiao Ming finish these tasks at the earliest in order to let the guests have tea early? ( )
(A) 20 minutes (B) 19 minutes (C) 18 minutes (D) 16 minutes.
Second, be serious. You can fill in these blanks (***32 points, 4 points for each small question).
The least common multiple of 1, 4,6 is.
2. Xiaoming planted 125 trees this spring, but 5 trees didn't survive, and the survival rate was.
3. After the summer vacation, the schoolbags in 30 yuan will be sold at a discount of 60% RMB.
4. Fill in the blanks with numbers: meticulous; Sleeve breeze;
Gu Maolu; The inner journey begins with a small step.
6. Fill in appropriate numbers according to the law: 1, 1, 2, 3, 5, 8, 2 1.
7. Since the founding of New China, China has conducted five censuses. The following table is the national population statistics obtained from previous censuses:
Census year1953196419821990 2000.
Population (billion) 5.946.9510.081.3412.95.
The population of (1) 1953 is one billion, and in 2000 it was one billion;
(2) From 1953 to 2000, China's population increased by 1 100 million.
8. According to the 24-point algorithm, there are four numbers 1, 2, 3 and 4, and each number is only operated once. If the result is equal to 24, the formula = 24.
1. Fill in the blanks (each space 1, 30 stands for * * *).
A cube is surrounded by _ _ _ faces, with _ _ _ vertices and _ _ _ edges. A cylinder is surrounded by _ _ _ faces.
3. If 5℃ above zero is recorded as +5℃, then 3℃ below zero is recorded as _ _ _ _.
3. If a < 0, then a _ _ _ _ 2a (fill in the blanks with, =).
4.74, in the cardinal number is _ _ _ _ _ _, the index is _ _ _ _ _, in (-2) 3, the cardinal number is _ _ _ _ _ _ _ _ _.
⒌(- 1)2000=__________, (- 1)200 1=___________,- 12002=_____________。
6.A minus 70 15% can be expressed as _ _ _ _ _ _ _ _.
If the side length of a cube is a, then the volume of the cube is _ _ _ _ _ _ _, and the surface area is _ _ _ _ _.
⒏ The single digit of a two-digit number is A and the ten-digit number is B. Please use an algebraic expression to indicate that this two-digit number is _ _ _ _ _ _ _ _ _ _ _ _.
(9) The lengths of the three sides of a triangle are 2x, 4x and 5x respectively, and the circumference of this triangle is _ _ _ _ _ _ _ _ _.
⒑ In three consecutive even numbers, n is the smallest one, and the sum of these three numbers is _ _ _ _ _ _ _.
5. Please explain the meaning of the following algebraic expressions:
6P:_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
a2-B2:_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ .
25a+ 12b:_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ .
5] The price of a commodity is X yuan, so 1/2x can be interpreted as _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.
12、( 1) 0.25 =_____′_____〃 (2) 1800〃=_____′_____
⒔ Fillet = _ _ _ _ _ Flat angle = _ _ _ _ Right angle = _ _ _ _ _ _ degrees.
Second, true or false questions (65438+ 0 points for each question, ***6 points)
1, rational numbers are divided into positive numbers and negative numbers. ( )
2. The absolute value of rational number must be greater than 0. ( )
3 、( 3x-2)=-3x-2()
4、8x+4= 12x()
5、3(x+8)=3x+24()
6、3x+3y=6xy()
Choice (2 points for each small question, *** 12 points)
1, if | a |a|=4, then a = ()
A, 4 B,-4 C, 4 or-4 D, neither.
2, the reciprocal of -3/8 is ()
a 、-3/8 B、8/3 C、8/3 D、3/8
3. subtract 3 from the number n and enlarge it by 5 times. The final result is ()
a、n-3×5 B、5(n-3) C、n-3+5n D、5n-3
4. In a class * * *, there is student A, of which 35% are boys, so the number of girls is ().
a、35%x B 、( 1-35%)x C、x/35% D、x/ 1-35%
5. Point out the shape symbol () of the geometric section in the drawing.
A.B. C. D。
Three. Calculation (3 points for each small question, *** 12 points)
1、( 1/3+ 1/4- 1/6)×24
2、0-23÷(-4)3- 1/8
3、(-2)3×0.5-(- 1.6)2/(-2)2
4、23÷[(-2) 3 -(-4)]
Four, simplify the following categories (3 points for each small question, *** 12 points)
1、2(2a2+9b)+3(-5a2-4b)
2、a+(5a-3b)-(a-2b)
3、3n-[5n+(3n- 1)]
4、a-(5a-3b)+(2b-a)
V. Simplify first, then evaluate (5 points for each small question, *** 10)
1, (3a2+7bc-4b2)-(5a2-3bc-2b2)+ABC, where a = 5, b = 1/3 and c = 3.
2. (5a2-3b2)+[(a2+B2)-(5a2+3b2)], where a =- 1 and b = 1.
Six, drawing questions (4 points for each small question, ***6 points)
1. As shown in the figure, please draw points A, B and C that are not in a straight line according to the following requirements:
B
A c
(1) Make a straight line AB
(2) for ray AC
(3) Line segment BC
3. As shown in the figure, it is the top view of the geometry built by several small cubes. The number in the small square indicates the number of small cubes in this position. Please draw the front view and left view of the corresponding geometry:
Seven, the operation problem (each small 6 points, *** 12 points)
Make a triangle with matchsticks, as shown below, and fill in the following table:
1. According to this rule, it takes _ _ _ _ times to build n such triangles.
Seven matchsticks can be used to put out the "8" in the picture. You can remove some of them and output the following figures:
Put a "6" to remove the _ _ _ _ _ _ _ root;
Put a "5" to remove the _ _ _ _ _ _ _ root;
Put a "3" to remove the _ _ _ _ _ _ _ root;
Output "2" to remove _ _ _ _ _ _ _ root.
I. Fill in the blanks (2 points × 15 points = 30 points)
In 1 and polynomial -abx2+x3-ab+3, the coefficient of the first term is and the degree is.
2. Calculation: ①100×103×104 =; ②-2a3b4÷ 12a3b2 = .
3 、( 8xy2-6x2y)÷(-2x)= .
4 、(-3x-4y) ( ) = 9x2- 16y2 .
It is known that the side length of a square is a, if its side length increases by 4, its area will increase.
6. If x+y = 6 and xy = 7, then x2+y2 =.
7. According to some data, the forest called "the lung of the earth" is disappearing from the earth at the rate of 65,438+0,500,000 hectares per year, and the area of forest disappearing every year is expressed as _ _ _ _ _ _ _ _ hectares by scientific notation.
8. The radius of the sun is 6.96× 104 km, accurate to _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.
9. Xiao Ming marks six numbers (1, 2, 3, 4, 5, 6) on the six faces of a small cube, and throws the small cube at will, then P (the number thrown is less than 7) = _ _ _ _ _.
10 and figure (1), when the cut ∠AOB increases 15, ∠COD increases.
1 1, as shown in figure (2), ∠1=10, then ∠ 2 = 0 (the top and bottom of the can are parallel to each other).
Figure (1) Figure (2) Figure (3)
12. There is a spotlight at the top of the parallel building. When the beams intersect, as shown in Figure (3), ∠1+∠ 2+∠ 3 = _ _ _ _ _
Second, multiple-choice questions (3 points ×6 points = 18 points) (carefully review the questions, beware of traps! )
13, if x 2+ax+9 = (x+3) 2, the value of a is ().
(A) 3 (B) 3 (C) 6 (D) 6
14, as shown in the figure, the length of the rectangle is a, the width is b, and the horizontally shaded part is a rectangle.
The other shaded part is a parallelogram, and their width is C, so the face of the blank part
The product is ()
(A) ab-bc+ac-c 2
(C) ab- ac -bc (D) ab-ac-bc-c 2
15, the following calculation ① (-1) 0 =-1②-x2.x3 = x532× 2-2 = ④ (m3) 3 = M6.
(5) (-A2) m = (-AM) 2 The correct one is ............................. ().
1 (B) 2 (C) 3 (D) 4。
Figure a figure b
16 As shown in the figure, the error in the following judgment is ().
(A)A+∠ADC = 180—→AB‖CD
(B)AB‖CD—→∞ABC+∞C = 180
(C) 1 =∠2—→ BC
(d) BC-3 = 4
17, as shown in figure b, the times of a‖b and ∠ 1 are half of ∠2, so ∠3 is equal to ().
(A)60(B) 100(C) 120(D) 130
18, the winning rate of a game is 1%, and Xiaohua bought a lottery ticket of 100. The following statement is correct ().
(a) I will definitely win the prize; (b) I will definitely not win the prize; (c) I have a high probability of winning the prize; My chances of winning the prize are slim.
Third, solve the problem: (write the necessary calculus process and reasoning process)
(1) calculation: (5 points× 3 =15 points)
19、 123? -124× 122 (calculated by algebraic expression multiplication formula)
20、9(x+2)(x-2)-(3x-2)2 2 1、0. 125 100×8 100
22. A liquid contains 10 12 harmful bacteria per liter, and 1 drop of insecticide can kill 109 such harmful bacteria. How many drops does this pesticide need to kill harmful bacteria in this 2 liters of liquid? If 10 drop of this pesticide is one liter, ask: How many liters of pesticide should be used? (6 points)
24. The complementary angle of an angle is 18 degrees, which is more than twice its complementary angle. What's the angle? (5 points)
Mid-term examination paper of seventh grade mathematics in 2007
(The full mark of this volume is 100, and the completion time is 90 minutes)
Name: Achievements:
1. Fill in the blanks (this big question * *, a total of 15 questions, 2 points for each question, out of 30 points).
1, as shown in the figure: the number whose distance from point A on the number axis is equal to 5 is.
2. It is correct to round 3. 14 15926 to one thousandth. If 302400 is expressed by scientific notation, it should be recorded as about 3.0× accurate to one decimal place.
3. It is known that the circumference of a circle is 50, and the radius of the circle is expressed by an algebraic expression containing π, which should be.
4. Each pencil is worth 1000000 yuan. After Xiao Ming bought n pencils with10 yuan, there was still RMB left.
5. When a =-2, the value of algebraic expression is equal to.
6. The algebraic expression 2x3Y2+3x2Y- 1 is a second-order term.
7. If 4amb2 and abn are similar terms, then m+n=.
8. Polynomials 3x3y- xy3+x2y2+y4+Y4 are arranged in ascending order by the letter X.
9. If it is ∣x-2∣= 1, then it is ∣x- 1∣=.
10, calculation: (a- 1)-(3a2-2a+ 1) =.
1 1. Calculate with a calculator (keep 3 significant figures): =.
12, Blackjack Game: Use the following numbers to score 24 points (each number can only be used once).
2, 6, 7, 8. Formula.
13, calculation: (-2a)3 =.
14, calculation: (x2+x- 1)? (-2x)= .
15. Observe the rule and calculate: (2+1) (22+1) (24+1) (28+1) =. The calculator doesn't work, and the result is in the form of power. )
Second, the choice (this big topic * * * a total of 4 questions, each question 2 points, out of 8 points)
16, the following statement is correct .................................................. ()
(A)2 is not algebraic; (b) it is a single item.
The linear coefficient of (c) is 1 (D) 1 is a monomial.
17. The following merged similar projects are correct ....................................................................... ()
(A)2a+3a = 5(B)2a-3a =-A(C)2a+3b = 5ab(D)3a-2b = ab
18, the following set of numbers arranged according to the law: 1, 2, 4, 8, 16, ..., No.2002 should be ().
A, b,-1 C, d, the above answers are incorrect.
19. If we know that A and B are reciprocal, and X and Y are reciprocal, then algebraic expression.
The value of |a+b|-2xy is ().
A.0b-2 c.-1d. cannot be determined.
Iii. Answer: (This big question is * * *, with a total of 4 questions, with 6 points for each question, out of 24 points).
20. Calculation: x+ +5
2 1, evaluation: (x+2) (x-2) (x2+4)-(x2-2) 2, where x =-
22. It is known that a is the smallest positive integer. Try to find the value of the following algebraic expression: (4 points for each small question, *** 12 points)
( 1)
(2) ;
(3) By (1), (2) What did you find or think of?
23. Given that a = 2x2-x+ 1, a-2b = x- 1, find b.
Four, the application problem (this big problem * * * has five questions, 24, 25 each question 7 points, 26, 27, 28 each question 8 points, out of 38 points)
24. It is known (as shown in the figure) that the side length of square ABCD is B, and the side length of square DEFG is A.
Find the area of (1) trapezoidal ADGF.
(2) the area of triangle AEF
(3) Area of triangular AFC
25. Known (as shown in the figure): use four right-angled triangles with base B, height A and hypotenuse C.
Make a square and find the area of the small square in the center of the figure. You can find it easily.
The area of the solution (1) small square =
Solution (2) Area of small square =
By solving (1) and (2), we can get the relationship between a, b and c as follows:
26. It is understood that the taxi charging standards in our city are as follows: if the mileage does not exceed five kilometers, 5 yuan will be charged; If the mileage exceeds 5 kilometers, the excess part will be charged at 1.2 yuan per kilometer except 5 yuan.
(1) If someone travels by taxi for x kilometers (x >: 5), how much should he pay? (Column Algebra) (4 points)
(2) A tourist takes a taxi from Xinghua to Shagou and pays 4 1 yuan. Try to estimate how many kilometers it is from Xinghua to Shagou. (4 points)
27, the members of the first team and the second team get together. There are m people in the first team, and the second team has two more people than the first team. If each member of two teams gives a gift to each member of the other team.
Q: (1) The total number of gifts given by all players. (represented by the algebraic expression of m)
(2) When m= 10, how many gifts are given?
28. The price of a commodity in 1998 is 5% higher than that in 1997, while the price in 1999 is higher than that in 1998, and the price in 2000 was lower than that in 1999. So, in 2000, compared with 1997, was it price increase or price decrease? What is the percentage of price increase or decrease?
In 2006, the first semester, the first grade, the mid-term exam.
Mathematics test paper answer
1. 1, 2, 10-Mn 3, -54,-1, 2 5, 5, 3, 6, 3
7、3x3y+x2y2- xy3 +y4 8、0、2 9 、-3a2+3a-2 10 、-a6
1 1 、-x8 12 、-8a3 13 、-2x3-x2+2x 14、4b2-a2 15、2 16- 1
2. 16, D 17, B 18, B 19, d.
Three. 20. Original formula = x+ +5 (1')
= x+ +5 ( 1 ')
= x+ +5 ( 1 ')
= x+4x-3y+5 ( 1 ')
= 5x-3y+5 (2 ')
2 1, the original formula = (x2-4) (x2+4)-(x4-4x2+4) (1')
= x4- 16-x4+4x2-4 ( 1 ')
= 4x2-20 ( 1 ')
When x =, the value of the original formula = 4× () 2-20 (1').
= 4× -20 ( 1')
=- 19 ( 1')
22. Solution: The original formula = x2-2x+1+x2-9+x2-4x+3 (1').
=3x2-6x-5 ( 1 ')
= 3 (x2-2x)-5 (2') (or 3x2-6x = 6 from x2-2x = 2).
=3×2-5 ( 1')
= 1 ( 1')
23. solution: A-2b = X- 1
2B = A-(x- 1) ( 1 ')
2B = 2 x2-x+ 1-(x- 1)( 1 ')
2B = 2 x2-x+ 1-x+ 1( 1 ')
2B = 2x2-2x+2 ( 1 ')
B = x2-x+ 1 (2 ')
24. Solution: (1) (2')
(2) (2')
(3) + - - = (3')
25. Solution: (1) C2 = C2-2ab (3')
(2) (b-a) 2 or b 2-2ab+a 2 (3')
(3)C 2= a 2+b 2 ( 1 ')
26. Solution: (25)2 = a2 (1')
a = 32 ( 1 ')
2 10 = 22b ( 1 ')
b = 5 ( 1 ')
Original formula = (a) 2-(b = (a) 2-(b) 2-(A2+AB+B2) (1'+0').
= a2- b2- a2- ab- b2 ( 1 ')
=- ab- b2 ( 1 ')
When a = 32 and b = 5, the value of the original formula =-× 32× 5 -× 52 =-18 (1').
If directly substituted: (8+1) (8-1)-(8+1) 2 =-18.
27. Solution (1): The first team gave the second team ***(m+2)? M pieces (2 feet)
Team two gave team one ***m? (m+2) pieces (2')
Two teams * * * give 2m? (m+2) pieces (2')
(2): When m = 2× 102+4× 10=240 pieces (2')
28. Suppose the commodity price of 1997 is X yuan (1').
The commodity price of 1998 is (1+5%)x yuan (1').
The commodity price in 1999 is (1+5%) (1+kloc-0/0%) x yuan (1').
In 2000, the commodity price was (1+5%) (1+10%) x yuan =1.0160%.
=0.0 164= 1.64% (2')
A: In 2000, the price ratio 1.997 increased by 1.64%. ( 1')