1. 12 tons = 800 kg () tons.
3.85 cubic meters = () cubic decimeter; 4 liters 40 ml = () liters
2. The largest three-digit number that can be divisible by 2 and 3 at the same time is ().
3. When X= (), the values of 4x-8 and 5x- 12 are equal.
The sum of the sides of the cube is 48 decimeters. The surface area of this cube is () square decimeter and the volume is () cubic decimeter.
The sum of numbers a and b is 8.5. If the decimal point of the number A moves one place to the right, it is exactly seven times that of the number B. The number B is ().
6. Fill in the appropriate unit name in brackets:
The volume of an eraser is about 8 (); One classroom accounts for about 48 ().
The volume of the car fuel tank is 30 (); The length of each step of Xiao Ming is about 60 ().
Among natural numbers within 7.20 (including 20), there are () odd numbers and () even numbers.
8. () is divisible by () in14,6,15,24, and () and () are prime numbers.
9. 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 ().
10.5 □ When () is filled to the maximum, this number can be divisible by 3, and the divisor of this number is ().
1 1. 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 ().
12. 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 ().
13. Cut a 2-meter-long rectangular steel into two sections along the cross section, and increase the surface area by 0.6 square decimeter. The volume of this rectangular steel is () cubic decimeter.
Second, judge.
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. ( )
Third, choose.
1. If a = 5b, the least common multiple of a and b is (). (A and B are both natural numbers)
a、a B、b C、ab D、5
2. The circumference of an isosceles triangle is 50 cm, the base length is 14 cm, and one waist is () meters.
a、36 B、22 C、 18 D、 1 1
3. The quotient of two numbers is 1.5, the dividend is reduced by 10 times, the divisor is expanded by 100 times, and the quotient is ().
a、 1500 B、0.00 15 C、 15 D、0.0 15
4. When the natural number A is divided by the natural number B, the quotient is 5, and the least common multiple of these two natural numbers is ().
A, B, B, C, V
5. The greatest common divisor of 5.a = 2× 2× 3 and b = 2× 3× 5ab is ().
a、6 B、3 C、2
6. The side length of the cube is enlarged by 3 times, and the volume is enlarged ().
A, 3 times b, 9 times c, 27 times
7. There are () two numbers greater than 0. 1 less than 0.2.
A, 9 B, 0 C, countless d, 99
8. Two decimal places are accurate to 5.0, and the minimum number of digits is ().
a、4.99 B、5. 1 C、4.94 D、4.95
9. Epiphyllum can last at least 4 hours, and the flowering time of wheat is 0.02 times that of Epiphyllum, which is about ().
A, 0.8 minutes b, 5 minutes c, 0.08 minutes d, 4 minutes 4. Calculate.
1. Write the number directly.
27 + 137 = 29 10 -3 10 = 35 + 0.4 = 3 14 + 156 =
4-259 = 720 -0.35 = 5 15 + 4 = 1 + 12 + 13 =
0.5 + 34 - 12 = 10 10 1 1 -3 + 1 1 1 1 = 434 -2.5- 14 =
2. Simplify the calculation if it can be simplified.
9-4.8÷6×0.5 2. 16÷[ 64.8-(5 1.3-2.7×3 ] ( 1.4×0.3 + 2.46)÷ 1.8
(2.5÷2 + 2÷2.5)×0.4 3.7 1 + 3.7 1× 17.4-8.4×3.7 1 1.2 + 8.8× 1.25
3. Solve the equation.
6.72- 1.2X = 1.44 4×(X+ 18)= 6×(X- 14)45 13-X = 2
x+2 12 = 3.25 x+( 123+ 16)= 4.5 578+x = 9
5. Column synthesis formula or equation calculation.
1.4.08 Subtract the product of 0.8 and 5, and divide the difference by 0.4. What is the result?
4 times of 2.4.5 is a number greater than 1.2 times, and 1.8. Find this number.
3. How much is the sum of156 and 429 less than 659? 4. What is the difference between1029 and the sum of 145 and 2.5?
6. Application questions.
1. There are two workshops, workshop A 132 people and workshop B 144 people. After transferring several people from workshop A to workshop B due to work needs, the number of people in workshop B is exactly twice that of workshop A. How many people should be transferred from workshop A to workshop B?
2. An iron oil tank with a cuboid cover is 3cm long, 3cm wide and 8cm high. How much iron does it take to make such a fuel tank? The fuel tank contains 0.85 kg of fuel per cubic meter. What is the maximum fuel quantity?
3. A group of students set out from school and went camping training outside the school. Each branch is 80 meters long. After walking for 22 minutes, the school will send an urgent notice to the captain. The correspondent started from school and caught up with him along the original road at a speed of 240 meters per minute by bike. How long will it take the correspondent to catch up with the team? (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 A and B is 120km. It took someone five hours to get from A to B by bike, and it took four hours to accelerate when he came back. How many kilometers per hour does he commute on average?
6. Make 12 rectangular iron chimney, each with a length of 2m, a width of 4m and a height of 3m. How many square meters of iron do you need at least?