Dear students, you are diligent and eager to show your talent in mathematics! Teachers provide a platform for you to show yourself. Please finish the following test paper within 90 minutes, and the teacher will give it to you.

You make a proper evaluation! Your grades

Ren Woxing in the palace of knowledge. (20%)

1 and 12047080 write (), and the mantissa after omitting ten thousand is about ().

2. If A is B, the least common multiple of A and B is (), and their maximum fractional factor is ().

3, 4.25 hours = () () is divided into 2 hectares and 40 square meters = () hectares.

4. A piece of wood is 1.6 meters long. Now, it will be sawed into small pieces of the same length. Seven sawed off, each piece accounts for () of this piece of wood, and each piece is () meters long.

The first group of students in class 5.6 (1) weigh 45 kg, 50 kg, 45 kg, 5 1 kg, 47 kg and 45 kg respectively. The mode of this set of data is () and the median is ().

6. There are 3 cm and 4 cm sticks. Please select 1 piece, the length is whole cm. The maximum circumference of a triangle is () cm and the minimum circumference is () cm.

7, there are three locks and three keys, now use three keys to open three locks, try () times at most.

8. A cube, in which four faces are painted red, one face is painted green and the other face is painted blue. Xiaoding throws it 10 times at will, and the possibility of blushing up after falling is ().

9. Cylinders and cones have equal bottoms and heights. If their volumes differ by 32 cubic decimeters, then the volume of the cone is () cubic decimeters.

The quotient of 10 and the number a divided by the number b is 1.5. If the number A is increased by 20, then the number A is twice that of the number B ... The original number of A is ().

1 1, a cylinder with a height of10cm, if the height is shortened by 3cm, its surface area will be reduced by 94.2cm2.. The volume of this cylinder is () cubic centimeters.

12, build a triangle with matchsticks, 1 triangle with 3 matchsticks, 2 triangles with 5 matchsticks and 3 triangles with 7 matchsticks. According to this rule, build 50 such triangles with () matchsticks.

Second, compare repeatedly and choose carefully. (Fill in the serial number of the correct answer in the brackets below) (10%)

1, any multiple of 5 in natural numbers ().

① It must be a prime number ② It must be a composite number ③ It may be a prime number or a composite number.

2. The ratio of the circumference of the cone to the bottom of the cylinder is 1: 2. The height of a cone is six times that of a cylinder, and the volume of the cylinder is conical (). ① Twice ② ③

3. The actual distance between Party A and Party B is 320km, and the distance measured on the map is 4cm. The scale of this map is () ①1:80②1:8000③1:800000.

4. If a \ = B×(a and B are not equal to zero), then ().

①a>b ②a=b ③a