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Academic Year 2003~2004 grade eight mathematics of the last term final tries
(Examine time:90 minutes, try a total 70 ★)
A, with meticulous care choose(each following of fully choose answer in, only an answer is correct, please right answer of the ordinal number stuff with brackets in and get a right answer 1 ★, the subject is total 4 ★)
1.Every kind of following estimate a result correct BE()
A.≈ 60.4 Bs.≈ 6.38 Cs.≈ 0.066 Ds.The ≈ is 96< BRs>
2.Can't pass basic sketch in four following sketches even move what to get BE()

3.In each following sketch, a kind of each sketches ability is airtight what to spread BE()
A.Triangle, positive six side forms with eight side form B.Arbitrarily triangle, square with positive six side formses
C.Rhombus, positive six side forms with positive eight side form D.Exact square, trapezoid with ten side forms
The 4. ABCDEFs is the steel plate of a piece of L form, the piece teacher wants to incise it 2 pieces of area equality, hence he designed as follows four kinds of projects.(The design way of thinking which grows a project each time is: L form steel plate is divided into regular square or complement as regular squares with the colourful pen, then makes sure hand over of a square diagonal line point, finally along lead two straight line ms that square diagonal lines hand over a point incise).Can incise the steel plate of this L form in piece four kinds of projects of teacher design two pieces of projects of steel plates of area equality have

A.1 the B.2 C.3 D.4
Two, concentrate to fill(get a right answer 1 ★, the subject is total 6 ★)
5.Of contrary number BE_____, of the reciprocal of arithmetic square root BE_____.
6.A polygon interior angle with is it of exterior angle with of 300%, then this polygon side number BE_____.
7.Like diagram, the area of rhombus ABCD is 24, diagonal line AC=6, then another diagonal line BD of rhombus ABCD of long is_____, the side is long is_____.

8.Such as the diagram, in the right angle sit the mark fasten, if each top of△ ABC of horizontal sit a mark constantly, the Zong sits marks to all multiply-1 after, get of the △ A ′ B ′ C ′ is in_____ the quadrant.

9.The classmate of Zhang Jia Hui4 within 7 days completion homework use of time is shown as watch below:(unit:cent)
Day time
1
2
3
4
5
6
7
Time
50
75
90
65
80
70
65
Time that her completion homework use of many number BE_____, median BE_____.
10.Have already known some A(2, a) with order B(-3, b) in the straight line y=-x+8 up, so all of the relation between an and b BE_____.
Three, elaboration calculate a calculate:(11~13 be 4 for each ★, 14 are 5 ★, the subject is total 17 ★)
11.Compute:.
12.Compute:(+2).(2-)
13.Solve a square distance set:
14.The side is long for 2 equilateral â–³ OBCs to sit a mark to fasten medium position to is shown as diagram in the right angle.
(1)Beg sit of each top of aâ–³ OBC mark;
(2)If round △ OBC the top O agreeable hour hand to revolve 90 °s, so sit of the △ OBC each top mark again is how much

Four, patiently say(the subject be total 5 ★)
15.Such as the diagram, O for hand over of rectangle ABCD diagonal line point, DE ‖ AC, CE ‖ BD.Excuse me, OE and CD be mutual perpendicular why

Five, diligently put together(the subject be total 5 ★)
16.The small Fang is the publicity member of committee of class, she prepares one period handwritten wall posters, need the colorful paper of an exact square, but she the colourful paper which found out 2 to is shown as diagram.(unit:Li rice)She moved some kind of brainses, shear to put together to get an exact square through these two pieces of papers, there is no surplus.You know she is how shear to put together of
(The trace which requests to reserve to shear to mow mark out a homologous data;Draw another shears sketch after put together and put together to repair of the part means with the shadow.)

Six, with concentration do(each 8 for each ★, the subject is total 24 ★)
17.In the right angle sit the mark fasten, two portraits of linear functions is shown as diagram.
(1)Beg straight line l 1, l 2 expression types;
(2)Solution these are two expression type constitute of square distance set;
(3)Observe the portrait hands over a sit of some A mark, and carry on a comparison with the solution of square distance set, you discovered what

18.After Liu2 Ming2's father be unemployeed, a garden pond which contracts for suburban area has already kept fish for two years and the first year threw in a certain fish fry 10,000.Caught 20 fishes from it in the autumn, call they of quality as follows:(unit:1000 gram)
1.15 1.04 1.11 1.07 1.10 1.32 1.25 1.19 1.15 1.21
1.18 1.14 1.09 1.25 1.21 1.29 1.16 1.24 1.12 1.16
(1)Beg the average quality(the precision arrive 0.01) of this 20 fishes;
(2)According to former experience, the become of fish fry lives the rate as 90%, this kind of fish which estimates inside fish pond about has how much 1000 grams
(3)If the market sale price of this kind of fish is each thousand grams of 5 dollars money, Liu2 Ming2's father contracts for the expenses of fish pond devotion to add up to 20,000 dollars, so Liu2 Ming2's father sell all of these fishes after, acquisition profits is how much
19.Some make there is AN in pharmaceutical factory, B is two production lines which produce to disinfect a liquid over the oxygen acetic acid, because market sale circumstance, only the A production line devotion use .2003 April, year, the people of the whole country is in the battle prevent and cure"SARS", in bar of epidemic situation proliferation, once needed urgently oxygen acetic acid disinfection liquid.4 a month after A production line already gave birth to 240 boxes of finished products lead oxygen acetic acid disinfect liquid, B production line starts throw to produce.Have already known A, B two production lines produce this kind of disinfection liquid 30 boxes with 40 boxes respectively everyday.
(1)Respectively beg since April, A, B the total yield y(box) of two production lines with from the B production line hurl produce hereafter the function of the x(day) its relation type use;
(2)Make one two above-mentioned portraits of functions in the right angle of underneath sit the mark fasten;
(3)The B production line hurl produce how much day later of total yield and A production line of total the yield be equal;
(4)Point out the 20th day respectively, 26 divas, which production line of total yield Gao.

Seven, the quiet mind consider(the subject be total 9 ★)
20.Some griculture industry and business limited company, the existing and white chicken is 20 tons, if is directly selling on the market and the ton can make a profit smooth 600 dollars each time;Make in to burn chicken sale, the ton can make a profit smooth 1800 dollars each time;Make into chicken can sale, the ton can make a profit smooth 2400 dollars each time.The production ability of that factory is: if make in to burn a chicken, can process 4 tons everyday;Make into the chicken can can process 2 tons everyday.Be subjected to the restriction of personnel and equipments, 2 kinds process a way and can't carry on in the meantime, suffer indignities condition restriction, these white chicken have to within 6 days all sales or put the last hand.The sale program member small piece draws up two kinds of projects:
Project 1:much make into chicken can possibly, the rest directly sells white a chicken;
Project 2:make into a part chicken can, the rest makes in to burn chicken sale, and by luck complete for 6 days.
You think a choice which project the best why
Make reference to answer and grade point standard
A, with meticulous care choose(subject 4 total small, each 1 ★, total 4 ★)
1.B 2.D 3.B 4.C
Two, concentrate to fill(subject 6 total small, each 1 ★, total 6 ★)
5.2, 6.8 7.8,5 8.The third 9.65,7010. ay B.
So, the yield of A production line compares the yield Gao of B production line;
When x=26, y A=1020(box), y B=1040(box), y A
So, the yield of B production line compares the yield Gao of A production line…………★★★★★★★★
Seven, the quiet mind consider(the subject be total 9 ★)
20.Solution:choose to use a project two acquisitions get of the profits be the most.
Project 1:much make into chicken can possibly, the rest directly sells white a chicken,
Then 6 day all production chicken can, the white of the rest(20-2 ×s 6) ton chicken directly sells,
The profits that the acquisition get is P 1=2 ×s 6 the ×s 2400+(20-6 ×s 2) × 600=33600(dollar)…………★★
Project 2:make into a part chicken can, the rest makes in to burn chicken sale, and by luck complete for 6 days.
Establish the x ton makes into chicken can and the y ton makes in to burn chicken sale,…………★★★
Then can list a square distance set according to the idea: …………★★★★★★
Solve…………★★★★★★★
Project 2 acquisition profitses are P 2=s 4 × 2400+16 × 1800=38400(dollar). …………★★★★★★★★
Because the P is 1< BRs>
Answer:that factory should alternative 2 the best. …………★★★★★★★★★
Solve a method 2:establish to produce chicken can for x day, produce to burn a chicken for y day,
Then according to idea, have to solve
Project 2 acquisition profitses are P 2=s 2 ×s 2 × 2400+4 ×s 4 × 1800=38400(dollar)