1. Fill in the blank: 24 points.

1, 3.85 cubic meters = () cubic decimeter 4 liters 40 ml = () liters.

2. Weld a cubic frame (excluding joints) with 48cm long iron wire. The surface area is () square centimeters and the volume is () cubic centimeters.

3. Fill in the appropriate unit name in brackets:

The volume of an eraser is about 8 (), and a classroom accounts for about 48 ().

The volume of the automobile fuel tank is 30 (), and the length of each step is about 60 ().

There are () odd numbers and () even numbers among natural numbers within 4.20 (including 20).

5. In14,6, 15 and 24, () is divisible by (), and () and () are prime numbers.

6. The largest two-digit number that can be divisible by 2, 3 and 5 at the same time is (), and the prime factor to decompose it is ().

7, 5□ When () is filled to the maximum, this number can be divisible by 3, and the divisor of this number is ().

8. If A is divisible by B, the greatest common divisor of A and B is (), and the least common multiple of A and B is ().

9. It is known that A = 2× 2× 3× 5 b = 2× 5× 7, the common prime factor of A and B is (), and their greatest common divisor is ().

10, a 2-meter-long rectangular steel, cut into two sections along the cross section, and the surface area is increased by 0.6 square decimeter. The volume of this rectangular steel is () cubic decimeter.

Second, judgment: 5 points

1, nonzero natural numbers are either prime numbers or composite numbers. ( )

2. The multiple of a number must be greater than its divisor. ( )

3. The product of two prime numbers must be a composite number. ( )

4. A cuboid (excluding cubes) has at most 8 equilateral sides. ( )

5. Even numbers greater than 2 are composite numbers. ( )

Iii. Choice: 10.

1, natural number A divided by natural number B, the quotient is 5, and the least common multiple of these two natural numbers is ().

a . a . b . c . 5

2. The greatest common divisor of 2.A = 2× 2× 3b = 2× 3× 5ab is ().

A.6 B.3 C.2

3. The side length of the cube has been expanded by 3 times, and the volume has been expanded by ().

A.3 times B.9 times C.27 times

4, 15 and () are prime numbers.

A. 18

Four. Calculation: 24 points

(1) Find the greatest common divisor (except 3 numbers) and the least common multiple of the following groups by short division.

16 and 24 45 and 60 26 and 39

10, 15 and 45, 12, 14 and 42.

(2) Recursive equation calculation:

2.9× 1.4+2×0. 16 200-(3.05+7. 1)× 18

30.8÷[ 14-(9.85+ 1.07)] (2.44- 1.8)÷0.4×20

Verb (abbreviation of verb) application question: 37 points, 7 points for the second question, and 6 points for the other party.

1, a piece of rectangular steel, 1.6 meters long, with a cross section of 4 cm square. It weighs only 7.8 grams per cubic centimeter. How much does this square steel weigh?

2. Make an uncovered cuboid oil drum with iron sheet. The length and width are 4 decimeters and the height is 6 decimeters. How many square decimetres is the iron sheet? Put gasoline in a barrel, and each liter of oil weighs 0.82 kg. How many kilograms of gasoline can this barrel hold?

3. Forging a cubic billet with a side length of 0.6m into a rectangular steel with a cross section of 0.09m2 How long is the forged steel? (Equation solving)

4. A cuboid glass cylinder, measured from the inside, is 40 cm long and 25 cm wide, and the water depth in the cylinder is 12 cm. After a stone is immersed in water, the water surface rises to 16 cm, and the volume of the stone is found.

5. The distance between Party A and Party B is120km. It took someone five hours to get from A to B by bike, and it took four hours to speed up when he came back. How many kilometers does he drive per hour on average?

6. Make 12 rectangular metal chimneys, each section is 2m long, 4m wide and 3m high. How many square meters of metal should be used at least?

Six, thinking about the problem:

Saw a block of 8 cm long, 12 cm wide and 5 cm high into a cube of 2 cm long. How many pieces can you saw?