(1) is to divide () into () shares on average, and that's it. (1.5 points)

(2) The decimal unit is (), and it has () such decimal units, which is the smallest prime number after subtracting () such decimal units. (1.5 points)

(3) There are 30 boys and 24 girls in a class. The number of girls is () of the number of boys, and the number of boys accounts for () of the class. (3 points)

(4) Write all the simplest true fractions () with a denominator of 6, and write two false fractions () equal to 1. ( 1)

(5)()⊙()= = () (decimal). (2 points)

(6) The largest two-digit number that is a multiple of 2, 3 and 5 at the same time is (), and the prime factor to decompose this number is (). ( 1)

(7) () and () are prime numbers, their greatest common divisor is (), and their least common multiple is (). (2 points)

(8) Put two cubes with side length of 1 decimeter into a cuboid. The surface area of this cuboid is () and the volume is (). (2 points)

(9) A number is both a multiple of 12 and a multiple of 18, and the minimum number is (). ( 1)

(10) Cut a 3-meter-long square steel into three sections, increase the surface area by 80 square centimeters, and the original volume of the square steel is (). ( 1)

2.a, B, C, D, I will choose. (Fill in the serial number of the correct answer in brackets, 5 points)

(1) Cut the 4m-long rope into 5 segments on average, each segment accounting for ().

a，m b，m c，d，

(2) The following fraction that cannot be converted into a finite fraction is ().

A, B, C, D,

(3) Fractions with the same denominator ().

A, the decimal units are the same; B, the scores are the same; C contains the same number of decimal units.

(4) The numerator and denominator of the simplest fraction ().

A, all prime numbers B, one prime number and the other composite number C, and only the common factor is 1.

(5) Reduction and generalization are based on ().

A, the relationship between fraction and division B, the basic nature of fraction C, the unit of fraction

Third, strict judges. (Mark "√" for the right and "×" for the wrong, 5 points)

(1) There is only one score greater than and less than. ( )

(2) Divide the unit "1" into several parts, and the number representing such a part or parts is called a fraction ().

(3) According to the number of divisors, natural numbers can be divided into prime numbers and composite numbers. ( )

(4) Cubes with a side length of 6 decimeters have the same surface area and volume. ( )

(5) The smaller the denominator of a fraction, the smaller the decimal unit. ( )

Four, strive to become a psychic (28 points)

1, solve the equation. (8 points)

① X + 3.5=7 ② 4.8 - X = 2. 1

③ 2.7X- 1.6 = 38.9 ④ X÷4.5 = 20

2. Calculation of the following problems can be simplified. (16)

( 1)5.24+(9.78-4.24) (2)27-6.75-3.25

(3) 68- 7.5 + 32-2.5 (4)7.8× 10. 1

3, only formulas or equations, no calculation. (4 points)

(1)4.5 minus the sum of 0.2 and 1.98, what's the difference?

(2) 3.6 times a number is 8 and less than 72.72. What's this number?

V. Practical operation (9 points)

1. Match the left and right questions in the following groups with the results with "":(3 points)

1)① In 35 = 5× 7, 5 and 7 are (1) factors of 35.

② In 6× 8 = 48, 6 or 8 are both prime numbers.

(3)1,2, 4 and 5, of which 2 and 5 are prime factors of (3).

2)① Numbers with only one divisor are (1) prime numbers.

② A number with only two divisors is (2) a composite number.

③ Numbers with more than three divisors are (3) 1.

2. Draw a picture (6 points).

(1), the figure below is a cuboid with a length of 4 cm and a width of 1 cm. Please draw it into two equal cuboids to maximize its surface area.

(2) Draw the bottom surface and front surface of a cuboid on the lower grid paper, and calculate its bottom surface area and cuboid volume. (The side length of each small square is 1 cm)

The bottom area of this cuboid I drew is () square meters. The volume of a cuboid is () cubic centimeters.

Apply knowledge to answer the following questions. (6 points for each small question, ***30 points)

1, Yang Yang cut a cake into three pieces on average and ate one of them; Liangliang cut the same cake into 12 pieces on average and ate three pieces. Which of them has the bigger cake left?

2. Zhang Weidong plans to finish 20 math problems before the weekend, and has finished 16. How many points are left to complete?

3. In a swimming competition, Mingming swam 28 meters in 30 seconds, Qiang Qiang swam 23 meters in 25 seconds and Gong Hong swam 19 meters in 20 seconds. Who swims fastest and slowest among the three people?

A room is 8 meters long, 5 meters wide and 3 meters high. If the walls of the room are covered with wallpaper, excluding the doors and windows of 10 square meter, the wallpaper of 12.5 yuan is used per square meter. How much is the wallpaper of * *?

5. There are three steel wires with lengths of 12m, 18m and 30m respectively. Now, we must cut them into small pieces of the same length, but none of them are allowed to stay. What is the longest length of each piece? How many segments can a * * * be cut into?