1. If it drops 5 meters and is marked as -5 meters, then it rises 4 meters to be () meters; If +2kg means an increase of 2kg, then -3kg means ().
2. The radius of the cylinder bottom surface is 5cm, the height is 10cm, the bottom area is () cm2, the side area is () cm2, and the volume is () cm3.
3. The base and height of the cone and cylinder are equal. The volume of the cone is 76cm3, and the volume of the cylinder is () cm3.
4. If 5a=4b(b≠0), then a∶b =()∴ ().
5. The scale on the right indicates that 1 cm on the map is equivalent to the actual distance () kilometers on the ground. Rewrite it to the numerical range of ().
6. The price of each TV set is fixed, and the number of TV sets purchased is directly proportional to the amount of money.
7. The cylinder and the cone are equal in height, and the sum of their volumes is 72 cubic decimeters, so the cone volume is ().
8. Make a cylinder with a rectangular iron sheet with a length of 4.5 decimeters and a width of 1.2 decimeters. The transverse area of this cylinder is () square decimeter. (excluding interface)
9, if you want to show the changes of various quantities, choose () statistical chart is more appropriate; If you want to show the relationship between each part and the whole, it is more appropriate to choose () statistical chart.
10. There are five red balls and five yellow balls of the same size in the bottle. If you want to touch the ball, there must be two balls of the same color, and at least () balls must be touched.
Second, the judgment question; (Yes, hit "?" , wrong number "?" , 65438+ 0 points for each small question, ***6 points)
1, cuboids and cylinders with equal bottoms and heights must have the same volume. ( )
2. In proportion, if the product of two outer terms is 1, then the two inner terms must be reciprocal. ( )
3. If A is half of B, A is inversely proportional to B ... ()
Xiaoming's height is directly proportional to his weight. ( )
5. A map, in which the distance of 8cm indicates the actual distance of 8km. The scale of this map is 1: 100000. ()
6. In the salt water with salt content of 25%, the ratio of salt to water is 1: 3 ().
Three, multiple-choice questions (each question has only one correct answer, each question 2 points *** 12 points)
1, in the following groups, two ratios can form a ratio ().
A:6:5 and 12: 8 b: c: d:
2. The radius of the cylinder bottom surface is enlarged by 2 times, and the height is reduced by 2 times. Its volume ()
A: 2 times smaller B: 2 times larger C: 4 times larger D: unchanged.
3. It takes 10 minutes to saw a piece of wood into three sections and () minutes to saw it into six sections.
A: 5 B: 15 C: 25 D: 10
4, rewrite the line segment scale into numerical scale is ()
a: 1:60 B: 1:6000000 C: 1:60000D: 1: 180
5. On the axis,-on the () side of-18.
A, left b, right c, north d, uncertain
6. If 10 children are divided into 4 classes, at least one class will be divided into at least () students.
A. 1
Fourth, calculate the perimeter of the following circle. (8 points)
1. The diameter is 6 square centimeters. The radius is 5 decimetres.
5. Calculate the area of the following circle. (8 points)
1. The radius is 8cm2. The circumference is 9.42m (π is 3. 14).
Six, the application problem (1 problem 8 points, the rest of each question 6 points)
1. A wire can form a circle with a radius of 3 cm. If this line is re-enclosed into a square, what is the side length of this square?
2. Enclose a cylindrical grain depot with mats. The ground circumference is18.84m. How big is the grain depot?
3. A factory club has a circular dance floor with a circumference of 37.68 meters. Now it is planned to widen the perimeter by 1 meter. How much can the dance floor area be increased?
4. Two pulleys are connected together. The diameter of the big pulley is 0.54m, the radius of the small pulley is 0.09m, and the big pulley rotates five times. How many turns does the small pulley turn?