Fill in the blanks

1. After the woodworker finishes the door frame, in order to prevent deformation, two diagonal battens are often nailed, as shown in the figure. The mathematical reason for this is _ _.

2. In the subtraction formula, the sum of the minuend, subtraction and difference is 240, and subtraction is 3/5 of the difference. Then the difference of this subtraction formula should be ().

3. 3/4 of A is equal to 2/3 of B, and the simplest ratio of A to B is (): ().

4. A three-digit number, its single digit is A, its ten digits are B, and its hundred digits are C, so it should be recorded as ().

5. Divide the 8-meter-long iron wire into 5 pieces, each piece is 1 () and 3 meters (), each piece is () meters long.

6. Li Shifu assembled a TV set, and the work efficiency increased by 1%, so the time was reduced ().

7. There are two natural numbers, the greatest common divisor is 8 and the least common multiple is 240. These two natural numbers may be (), () or ().

8. For a basket of apples, each person is divided into two surpluses 1, three surpluses 1 and four surpluses 1. There are at least () apples in this basket.

9. For the simplest fraction, the sum of numerator and denominator is 92. If 16 is subtracted from both the numerator and denominator, the simplified score is 1/3, which is the simplest fraction ().

10, carefully observe the following figures and fill in the appropriate figures.

( 1)2,3,5,8, 13,( ),( ),34,

(2)2,6, 12,20,( ),42,

11.19970701pronounced as (). Rounding to ten thousand places is () ten thousand.

12.8 tons 50 kg = () tons; 2.4 cubic decimeter = () cubic decimeter () cubic centimeter

The decimal unit of 13.7/ 12 is (), and it has () such decimal units.

14. The smallest composite number is (), and its reciprocal is ().

The least common multiple of 15. 12, 18 and 24 is (). The greatest common divisor of 12 and 18 is ().

16. The ratio of peach trees to pear trees in the orchard is 5: 3. There are 40 peach and pear trees, () peach and () pear trees.

17. () The statistical chart can not only show the quantity, but also clearly show the change of the quantity.

18.6 may be the least common multiple of two numbers, please write them all separately; ( )。

19. A rope was cut and then connected for 9 meters, and the result was longer than the original. This rope was originally () meters long.

20. A rectangular piece of paper, the length of the long side is 19 cm, cut off the largest square, and the circumference of the remaining small rectangular paper is ().

2 1. 10098400 is pronounced as (), rounded to tens of thousands of digits is ().

22. When a number is divided by 2, 3 and 7, the result is 1, and the minimum number is ().

23. The product of two prime numbers is even, and one of them must be ().

24.20kg is 20% lighter than (). () meters are longer than 5 meters.

25. Four times the number of A is the number of B, and the ratio of A to B is ().

26. Cut a section of wire, that is, a wire () meters long, and then connect it for 4 meters. The result is longer than the original wire.

27. The average of A and B is 16, and the average of A, B and C is 20, so the number of C can be calculated as ().

28. The price of a commodity is reduced by 10% during the promotion period, and the price is increased by 10% after the promotion. At this time, the commodity price is the original price ().

29. A work started in June 1 was originally scheduled to be completed in one month. In actual construction, the task was completed on June 25th, and ()% was overfulfilled by June 30th.

The surface area of a cuboid is 4000 square centimeters. If the cuboid is cut into two equal cubes on average, if two such cubes are put together to form a cuboid, the surface area of the cuboid is at most ().

3 1, a number is 2 1, b number is 30, and a number is less than b number ()%.

There are 29 students in grade five, more than girls 16%, and girls have ().

33,365.5505 Writing ().

34. A triangular vegetable field has a side length ratio of 3: 4: 5 and a circumference of 84 meters, of which the shortest side length is () meters.

35, the ratio of the circumference of the circle to the diameter is ()

36, 3.6 hours = () when () points.

37. It takes 4 days for Party A to complete the same work alone, and 5 days for Party B. The efficiency of Party A is ()% of that of Party B.

38, sampling inspection of a commodity, there are 38 kinds of qualified, 2 kinds of unqualified, the qualified rate of this commodity is ().

39, 7/8: 1.75 The simplest integer ratio is (), which is ().

40. The hour hand of the wall clock is 5 cm long, and its tip has gone () cm all night.

4 1. The base of the triangle is 4cm long and 2cm high. The ratio of the area of this triangle to the area of a parallelogram with the same base height is ().

42. Two-thirds of A is equal to three-quarters of B, and the simplest integer ratio of A and B is ().

Second, multiple-choice questions:

1. Fill a number in the () of the four-digit 12() 0 so that it can be divisible by 2, 3 and 5 at the same time. There are at most () filling methods.

A.2b.3c.4d Countless

2. The school is 500 meters away from Xiaoming's home and 300 meters away from Xiao Juan's home. Xiaoming and Xiao Juan are separated by ().

It is uncertain whether it is 200m B 800 C 200 or 800m D.

3. The bottom area and volume of cylinder and cone are equal, and their height ratio is ().

A 2: 1 B 1:3 C 3: 1

It takes 6 minutes to saw a piece of wood into 3 segments, so it takes () minutes to saw it into 4 segments.

A.8 B. 9 C. 12

5, in the following formula, can't find the circular area is ().

a、πr2 B、πd2/4 C、πd2/2

6. The radius of the semi-circular flower bed is represented by the letter R, so its circumference is ()

a、r(π+ 1) B、r(π+2) C、2r(π+ 1) D、2(π+r)

7. In June, the temperatures in our city were 1 3℃, 18℃, 24℃ and 17℃ at 2: 00, 8: 00, 14: 00 and 20: 00 respectively. The average temperature on this day is ().

a、 1 1℃ B、29℃ C、 18℃ D、 14.5℃

8. A map, with a 0.5 cm long line segment representing the actual distance of 5 kilometers, the scale of this map is ().

9. 1280 can only be divisible by 2, 3 and 5 at the same time, at least () should be added.

a、 1 B、2 C、5 D、 10

10. The difference between two numbers is equivalent to 40% of the minuend, and the ratio of the minuend to the difference is ().

a、3:2 B、2:3 C、3:5 D、5:2

1 1. Enclose the following figure with iron wires of the same length, and () has the largest area.

A. triangle b square c rectangle d circle

12. Count, there are () line segments in a * * in the figure.

A.4 B. 6 C. 8 D. 10

13. Given that 4x+6= 14, 2x+2= ().

A. 10 B. 8 C. 6 D. 4

14. A pumpkin weighs about 4000 ()

Cm kg cm cm cm cm cm cm cm cm cm cm cm.

15. Two ropes of Party A and Party B were cut, and the rice was cut by Party B, leaving the iron wire ().

A.A is shorter than B. A and b are equal in length. C. A is longer than b.d. Not sure.

16. Add 6 grams of salt to 30% brine, and the percentage of salt in this brine is ().

A. more than 30% B. equal to 30% C. less than 30%

17. If the number of A is equal to three times the number of B, then the number of A () is the number of B.

A.& gtB. = C. & lt

18. If the area of the circle is enlarged by 16 times, the circumference will be enlarged ().

A. 16 times B.32 times C.4 times

Third, true or false:

1. Two proportions can form a proportion.

2. The length of the cube is 24cm and the volume is 8cm.

3. Two triangles with equal areas form a parallelogram.

A is longer than B, and B is shorter than A. ..

5. If a>b>0, it must be less than.

6. If you work 8 hours a day, the time spent assembling a bicycle is inversely proportional to the number of bicycles assembled. ( )

7. Because 3 ÷ 1.5 = 2, 3 can be divisible by 1.5. ( )

8. Bar charts can not only represent quantity, but also represent the change of quantity. ( )

9. Subscribe to China Youth Daily in direct proportion to the money spent. ( )

10. The sum of subtraction and difference is equal to the sum of minuend, subtraction and difference 1/2. ( )

1 1. If A divided by B equals 5 divided by 3, then A is 3/5 of B .. ()

12. The product of a number multiplied by a fraction is less than the multiplicand. ( )

13. The diameter is the longest line segment in a circle. ( )

14.4 and 0.25 are reciprocal. ( )

15.A and b are natural numbers, because A ÷ 3/4 = B × 4/5, so A >；; B. ()

16. The circumference of any circle is always π times its diameter. ( )

17. Remove the zero after the decimal point, and the size of the decimal point remains the same. ( )

18. Two numbers are prime numbers, and the least common multiple of these two numbers is their product. ( )

Fourth, ask questions about the text

What is the difference between the sum of 1. 12 and 36 minus the quotient of 1.2 divided by 3.6?

2. A number is 12 15 times. Find this number.

3. 40% of a number is less than 3 times of 10. Find this number.

4. A number is 1.2 greater than 30% of 40. Find this number.

5。 18 minus 1/3?

V. Comprehensive application problems

1. In order to "strengthen their physique and fight against SARS", Li Wei and Zhao Bing go running on the circular track of the stadium every morning (pictured). It is known that the circular runway is 400 meters a week, and two people are running in A and B, which are 100 meters apart. Li Wei runs 60 meters per minute, and Zhao Bing runs 40 meters per minute. They didn't meet until a few minutes after they started.

2. The radius and height of the bottom of the cylinder are 2 cm. Immerse it in the water of a uniform water tank, and the water level will rise by 4 cm. A cone with a bottom radius of 3 cm was immersed in water, and the water level rose by 4.5 cm. Find the height of the cone.

3. Team A and Team B completed14 of a project. At this time, Team B has something to do, and the rest will be done by Team A alone. 15 days. How efficient is Team B?

4. A rope was cut off for 5/9 of its total length for the first time, and the ratio of the length cut off for the second time to the length cut off for the first time was 9: 20, leaving 7 meters. How many meters did this rope grow?

5. Two cars, A and B, leave from AB respectively at the same time. Five hours later, the two cars met at a distance of 35 kilometers from the midpoint. At this time, the ratio of the distance traveled by A and B is 5: 4. What are the speeds of A and B?

6. Happy primary school life is coming to an end. Four students in Class 6 (2) agreed to water the saplings of their alma mater in the summer vacation. The number of trees watered by the first student is half of the total number of trees watered by other students, the number of trees watered by the second student is 1/3 of the total number of trees watered by other students, the number of trees watered by the third student is 1/4 of the total number of trees watered by other students, and the fourth student just watered them.

7. When salt is dissolved in water, salt water is formed. At present, there are 2000 grams of salt water containing 10%, and the concentration should be increased as needed to make the salt content reach 20%.

(1) What feasible methods do you think can be adopted? (List at least two)

(2) Choose a method and specify it by calculation.

8. Zhang Hua and Li Ming are practicing running on the circular track. At the same time, start from one point and take another road. When they met, Zhang Hua ran 250 meters and Li Ming ran 150 meters. How many meters will Li Ming run to reach the starting point when Zhang Hua reaches it?

9. The area of the parallelogram below is 36 square centimeters. Find the area of the shaded part.

10. Passenger cars and trucks leave from A and B relatively simultaneously. Three hours later, the bus has traveled 60% of the whole journey, and the truck is 30 kilometers away from the midpoint of the whole journey. As we all know, the speed of a bus is 24 kilometers more than that of a truck, so find the distance between A and B.

1 1. The side length of a large square is 13 cm, and the side length of a small square is 9 cm. What is the area of the shadow area (as shown below)?

12. The machine tool factory produced 2600 machine tools this year, 400 more than last year. How many machine tools did it produce last year?

13. It takes 10 hour to fill a pool, 12 hour to fill a pool, and 30 hours to drain a pool. If three pipes are opened at the same time, how many hours will it take to fill an empty pool?

14. A bus goes from place A to place B at a speed of 75 kilometers per hour and is expected to arrive in 3 hours. After driving 1 hour, the machine broke down and was repaired on site for 20 minutes. How many kilometers should I accelerate every hour to arrive on time without delay?

15. The weight ratio of goods in warehouse A and warehouse B is 7:8. If the goods are delivered from warehouse B and 6 tons are brought in from warehouse A, then warehouse A is 14 tons more than warehouse B. How many tons are the original goods of warehouse A and warehouse B respectively?

16. The road construction team plans to complete a road in five days. 22% of the whole journey was completed on the first day, and 23% of the whole journey was completed on the second day. The distance ratio of the last three days is 4:4:3, and the last day is 27 meters. How long is this road?

17. An alloy contains 3:4 copper and zinc, and 63 grams of new alloy with copper-zinc ratio of 1:2 was made from this alloy. How many grams of copper or zinc should I add?

18. The diameter of motor drive wheel for threshing is 0. 16m, and the diameter of thresher drive wheel is 0.24m If the motor rotates 3600 revolutions per minute, how many revolutions per minute will the thresher wheel rotate?

19. A junior high school student held a spring outing. If 45 buses are rented, 15 people have no seats. If the same number of 60 buses are rented, one bus is empty. It is known that the rent of bus No.45 is 220 yuan, and that of bus No.60 is 300 yuan.

Q: (1) How many students are there in this school?

(2) What is the most economical way to rent a car?

20. The typist types a manuscript. On the first day, I typed 25% of the total, on the second day, I typed 40% of the total, and on the second day, I typed 6 more pages than on the first day. How many pages are there in this manuscript?

2 1. There are 540 boys in the school, and 60 of them are less than 5/6 of the girls. How many girls are there in the school?

22. For a pile of coal, the ratio of tonnage transported on the first day to total tonnage is 1: 3. 4.5 tons were shipped the next day, and just half of the total tonnage was shipped in two days. How many tons is this pile of coal?

23. Make a rectangular water tank (without cover) with iron sheet, which is 3 meters long, 0.8 meters wide and 0.5 meters high. How many square meters of iron does it take? (The number is reserved for the whole square meter, and an approximate value is obtained in one way. )

24. If each park ticket is 8 yuan, is it enough for a school to organize 97 students to go to the park with 800 yuan?

25. It takes 20 hours to produce a batch of parts, and the working efficiency of B is 80% of that of A. If two people work together, how many hours will it take to produce 9/ 10 of this batch of parts?

26. There are 150 books in kindergartens in Le Tong, 40% of which are allocated to large classes, and the rest are allocated to small classes and middle classes according to the ratio of 4: 5. How many books are there in the small class and the middle class?

27. Two workshops 150 people. If 50 people are transferred from the first workshop, the number of people in the first workshop is 2/3 of that in the second workshop. How many people are there in workshop 2?

28. Look at the picture and fill in the blanks:

Xiaohua borrows books from the library 5 kilometers away from home by bike. As can be seen from the statistical chart given by the dotted line, Xiaohua gets () points for parking on the way to the library and () points for borrowing books from the library. The average speed from home to the library is () kilometers per hour. Home from the library, () kilometers per hour.