1. Calculation: 8+98+998+9998+99998 = _ _ _ _ _.

2. Add three different numbers after 947 to form the smallest six digits that can be divisible by 2, 3 and 5 at the same time. This number is _ _ _ _.

3. Please give five prime numbers, arranged in the order from small to large, so that the difference between every two adjacent numbers is 6. _ _ _ _ _ _ _ _ _ _ _.

4.

There are two rectangular pieces of paper of the same size, with a length of 10 cm and a width of 3 cm. Overlay and paste together as shown in the figure, and form a cross-shaped figure after pasting. Its circumference is _ _ _ _ _ _ _ _.

5.

100 times the product minus 5, the single digit of the difference is _ _ _ _ _.

6.

* * * There are _ _ _ _ triangles on the right.

7.

Subtract an integer whose last digit is not zero from a decimal. If you add a decimal point to an integer to make it a decimal point, the difference will increase by 154.44.

This integer is _ _ _ _.

8.

Two natural numbers

、

The greatest common divisor of is 14 and the least common multiple is 280. Their sum.

+

It's _ _ _ _.

Second, fill in the blanks. (4 points for each question)

1.

Calculation102 ÷ [(350+60 ÷15) ÷ 59×17] = _ _ _ _.

2.

Three students, A, B and C, discuss the sum of two prime numbers. A said, "The sum of two prime numbers must be a prime number." B said, "The sum of two prime numbers must not be a prime number." C said, "The sum of two prime numbers is not necessarily a prime number." Which of them is right? A: _ _ _ _ _ _.

3.

As shown below, four isosceles right triangles and 1 square form a rectangle. Suppose the area of a square is 1 cm2, then the area of this rectangle is (

) square centimeters.

4.

There are arrays: (1, 1, 1), (2, 4, 8), (3, 9, 27), ..., then the sum of the last two digits of the sum of three numbers in the 1998 group is _ _ _.

5.

A natural number greater than 1 is divided by 442, 297 and 2 10 respectively to get the same remainder, so the natural number is _ _

_。

6.

The price per kilogram of candy A, B and C is 9 yuan, 7.5 yuan and 7 yuan respectively. Now, 5 kilograms of candy A, 4 kilograms of candy B and 3 kilograms of candy C are mixed together. You can buy _ _ _ _ _ kilograms of this mixed candy with 10 yuan.

7.

There are at most five Sundays in a month, and there are at most five Sundays in _ _ _ _ _ months in 12 months of a year.

8.

There are 15 students, and each student has a serial number ranging from 1 to 15. 1 wrote a natural number, No.2 said "this number is divisible by 2", No.3 said "this number is divisible by 3", ..., and so on. Every student said.

Third, answer the question. (7 points per question)

1. There are 84 people in the Children's Palace Dance Team, which is three times more than the chorus, 15 people; A chorus of eight people in less than four times. How many people are there in the choir? (Using two methods to solve the comprehensive formula)

2. A project was completed in 30 days alone, and B in 40 days alone. Now two people are working together, and it takes 25 days to complete, during which A's rest days are twice that of B. B how many days off?

3. As shown in the following figure, cuboid container A contains 3744 cubic decimeters of water with a water depth of 14.4 decimeters. It is also known that the ratio of the bottom areas of rectangular container A and rectangular container B is 5: 3 (measured from the inside of the container). Now, put part of the water in rectangular container A into rectangular container B, so that the water depths of the two containers are equal. What is the water depth in the container at this time?

4. The old problem-building a canal is shown below. The circles 1, 2 and 3 respectively represent three wells, which are used to irrigate the following three fields. Need 1 well irrigation 1 field; No.2 well irrigates No.2 field; No.3 well irrigates no.3 field. How to repair the root canal of rectangular ABCD? Canals can't intersect. Please draw a schematic diagram.