Class name and grade time 80 minutes

A fill-in-the-blank question (1- 10)***23 points, each blank 1 point.

1. 10 and 5,5 can be () 10, 5 is the () number of 10, and 10 is the () number of 5.

The common multiple of 6 and 8 in 2. 50 is ().

The divisor of three. 24 is (), and the minimum multiple is ().

4. Natural number () is infinite, so there is no natural number (). [Small]

Sum of prime numbers within 5+0 5. 10 is ().

6. The minimum multiple of a number is 99, this number is (), and the prime factor of its decomposition is ().

7. 102 1 can be divisible by at least one integer ().

8. The natural number A is the divisor of the natural number B, the greatest common divisor of A and B is (), and the smallest common multiple is ().

9. The divisor of12 is (), where () is odd, () is even, () is prime and () is composite.

10. The least common multiple of two prime numbers is 143, which are () and (

) or () and ().

Second, true or false (2 points for each small question *** 14 points)

1. All numbers divisible by 2 are even numbers. ()

The divisor of 2. 20 is 2,4,5,10,20, ... ()

3. The prime factor of decomposition 75 is 3× 5× 5 = 75. ()

4. Because 4 and 9 are coprime, their greatest common divisor is 1 and their least common multiple is 36. ()

5. The sum of two odd numbers must be divisible by 2. ()

6. The product of several prime numbers is a prime number. ()

7. Numbers A and B are multiples of their greatest common divisor. ()

3. Fill in the serial number of the correct answer in (), with 2 points for each question and *** 18 points.

1. If the side length of a cube is reduced by 2 times, the sum of the side lengths must be reduced by 2 times, the surface area must be reduced (), and the volume must be reduced (). A 2 B 24 C 8 D 4

2, a maximum of 30 liters of gasoline tank, the () must be greater than 30 cubic decimeters.

A volume b volume c surface area d floor area

3. Eight small cubes are combined into a big cube, and one of them is taken at will. The surface area of this big cube is ()

A is big, B is unchanged, C is small, and D is uncertain.

4. The sum of the sides of a cuboid and a cube is equal. Given that the length, width and height of a cuboid are 6 cm, 5 cm and 4 cm respectively, then the volume of the cube () the volume of the cuboid.

A is greater than b, less than c, equal to d, and cannot be calculated.

5. Divide this cuboid block into two cubes with a side length of 4cm. The total surface area of the cubes () The cuboid surface area A is equal to B, greater than C and less than C..

6. cuboid wooden box volume and volume comparison ().

A. Same size B. Big size C. Big size D. Can't compare sizes

7. After sawing a 2-meter-long cuboid wood into two sections, the surface area increased by 100 cm2, and its volume was ().

A.200 cubic centimeters B. 10000 cubic centimeters c.2 cubic decimeters

8. After dividing a cuboid into several small cuboids, the volume ().

A. No change B. Bigger than before C. Smaller than before

9. The sum of the sides of a cube is 60 cm, and its surface area is ().

A.2 1600 cm2 B. 150 cm2 C. 125 cm3

Four. Fill in the form. (9 points)

Length, width, height, bottom area, surface area, volume cuboid 8 cm, 4 cm, 40 cm, cuboid 10 decimeter 120 decimeter 600 cubic decimeter cube 8 meter cube 54 square meters.

5. Look at the pictures and find their surface area and volume. (Unit: decimeter) (12 points)

Sixth, solve the problem. 24 points

1, a rectangular wooden box, 20 decimeters long, 7.5 decimeters wide and 3 decimeters high. How many square decimeters of wood do you need to make this wooden box?

The school needs to paint the new classroom. It is known that the classroom is 8 m long, 6 m wide and 3 m high, and the door and window area is11.4m2. If 6 yuan is painted every square meter, how much will it cost to paint this classroom?

3. A rectangular pool, its length, width and depth are 50m, 20m and 3m respectively. If the water depth in the pool is 1.5 m, how many cubic meters of water is there in this pool?

4. Cut a cuboid with a length of 12 cm, a width of 9 cm and a height of 5 cm into two cuboids. What are the maximum and minimum total surface areas of two cuboids?