(Duration: 80 minutes; Full volume 120 points)
The total score of the topic is one two three four five six.
score
First, the calculation problem. (28 points)
1, a number written directly. (4 points)
1945—798 = 1 104—87— 1 13= -0.0 1= 0.27÷2 =
1÷1= 3+7.37 = 6-75% =1.25 ÷1= 2. The calculation should be as simple as possible (18 points).
20.7-6 -6.68 64 ÷ 16 1.25×8.08
( + + )×34 5 ÷ +3 × 1. 1 0.24×7. 1+0.024×29
3. Find the unknown X. (6 points)
χ+0.68= 1 :χ= 0.05 :24 ×(χ+ 1 ) = 4
Fill in the blanks. (24 points)
(1) 266,305 is written as (), and "10,000" written by rounding is about ().
(2) 402,800 yuan, with "ten thousand" and "decimal point" removed, but its value unchanged, plus () zeros.
(3) The circumference of a semicircle is 10.28 cm, and the area of the circle where the semicircle is located is () cm2.
(4) The least common multiple of two numbers is 90 and the greatest common divisor is 15. These two numbers are () and ().
(5) The salt content in100g brine is 20g. When 20g pure salt is added, the salt content is about ()%.
(6) The average of the numbers A, B and C is 18, and their ratio is 1: 2: 3, so the sum of the numbers A and B is ().
(7) The radius and height of the cone bottom are enlarged by 2 times, and its volume is enlarged by () times.
(8) A cylinder with a bottom circumference of 25.12cm and a height 50% larger than the radius has a surface area of () cm2 and a volume of () cm3.
(9) Rectangular packing boxes with a bottom area of 4.8 square meters and transport side lengths of 0.6 m, 0.4 m and 0.5 m.. If you put two layers, you can pack at most () such boxes.
(10) 20% of the students in our class took part in the labor, and then four people took part in the labor, so the ratio of the number of people who took part in the labor to the number who did not take part in the labor was 1: 3, and there were () people in our class who took part in the labor.
(1 1) The volume ratio of cylinder and cone is 3: 5, the radius ratio of bottom surface is 3: 10, and their height ratio is (): ().
(12) The base length of an isosceles right triangle is 6 cm. Now, taking its bottom as the rotation axis, the volume of the three-dimensional figure obtained by rotating it once is () cubic centimeters.
Second, the judgment question. (Tick √ for the right and × for the wrong. ***5 points)
(1) Two lines that do not intersect are called parallel lines. ( )
(2) The circumference is directly proportional to pi. ( )
(3) A wire, first cut off, and then connected to the electric meter, the result is as long as the original. ( )
(4) If 7A = 5B, then a: b = 7: 5 ()
(5) Divide the 5m-long rope into 7 segments on average, and each segment is full length ().
Third, multiple choice questions. Fill in the correct answer number in brackets. 10)
The circumference of the (1) rectangle is 60 cm, and the length-width ratio is 3: 2. The area of this rectangle is () cm2.
a、 196 B、2 16 C、864
(2) The volume ratio of two cubes is 64: 27. Then the ratio of the surface areas of these two cubes is ().
a、4 :3 B、3 :4 C、9 : 16 D、 16 :9
(3) The area of the triangle is 27 square centimeters. It is known that the ratio of bottom to height is 3: 2. How many centimeters is it at the bottom? How many centimeters is the height?
A, 45 and 6 B, 6 and 9 C, 9 and 6 D, 6 and 45
(4) Check the germination of a batch of seeds, 50 seeds are selected for the first time, 40 seeds are germinated, and 30 seeds are selected for the second time, all of which germinate. The germination rate of these seeds is ().
a、B、80 % C、90 % D、87.5 %
(5) In the following four sentences, the correct statement is ().
A, the number A is more than the number B 10%, and the number B is less than the number A 10%. ..
B. If = 2, A and B are in direct proportion.
C, except prime numbers, natural numbers are composite numbers.
The real scores of d and less than are only,, and.
Five, geometry knowledge questions. (13)
(1) The area under the shadow accounts for the square area and the circular area. It is known that the area of the circular blank is 280 square decimeters larger than that of the square blank. Find the area of a circle. (5 points)
The picture below is the plan of a river. If you build a bridge across the river from point A, how to build the shortest bridge? Please draw it on the map. (represented by line segment AB) (6 points)
If the drawing scale is 1: 20000, please measure the length of the drawn line segment and calculate the actual length of the bridge in parallel.
After measurement, the length of AB in the figure is () cm.
Sixth, solve the problem. (***40 points)
(a) Only comprehensive formulas or equations are listed without calculation. (3 points each, *** 15 points)
1. There are more boys 14 and more girls than 8 in our class. How many people are there in the class?
2. Six tables and four chairs * * * pay 336.5 yuan. It is known that each set of tables and chairs needs a 60 yuan. How much is each table?
3. A worker produces 120 parts in 5 hours. According to this calculation, how many hours will it take to make another 80 parts? (List proportional expressions)
4. Cut a cylinder with a bottom diameter of 10 decimeter into two semi-cylinders along the bottom diameter, and increase the surface area by 80 square decimeters. What is the volume of this cylinder?
A factory now saves 0.8 tons of coal every day compared with the past. Coal burned in the past 18 days can now be burned for 30 days. How many tons of coal were burned every day in the past?
(2) Answer the following questions. (5 points each, ***25 points)
1. It takes Party A 4 minutes, Party B 5 minutes and Party C 6 minutes to complete the same number of parts. Now three people have completed 296 parts at the same time. How many parts did C make when it was finished?
2. A bus and a truck drive in opposite directions from two places at the same time. Bus trip 10 hour, truck trip 15 hour, the two meet at a distance of 75 kilometers from the midpoint. What is the distance between a and b?
3. Cast a cuboid iron block with a length of 9 cm, a width of 7 cm and a height of 3 cm and a cubic iron block with a length of 5 cm into a cylinder with a base diameter of 10 cm. What is the height of this cylinder?
4. Two cars, A and B, leave from the East and West Stations at the same time. 10 hours later, two cars meet and move on. Eight hours later, the A bus arrived at the West Station, and the B bus was 2 10 km away from the East Station. How many kilometers are the East Station and the West Station apart?
5. Li Shifu welded iron hoops for cylindrical barrels of the same size with metal wires. If 28 hoops are welded, the ratio of the length of steel wire to the total length is 8: 9; If 22 wires are welded, there are 57 meters left in this wire. How long is this wire?