I m an elementary school student and I d like to ask you a primary school math problem 10

So A = 2100 * (g.)

B = 2100 * (1 gram.)

C = 2100 * (2 grams.)

Ding = 2100 * (g.)

B + 1 B + 2 B + B = B = 2100

B = 262 A = B = 182

C = 2 B = 524

D = B = 1230

A: grams.

B: 1 gram.

C: 2x250=500g.

Ding: Grams.

A: 2100* (g.)

B = 2100 * (1 gram.)

C = 2100 * (2 grams.)

Ding = 2100 * (g.)

Set the need for A, BX, C, 2x, and D.

x = 250 A 175 g B 250 g C 500 g D 1175 g

Set the need for respectively:

A: B: KC: 2k

Ding: So: solution: k=250

A = B = k = 250g

C = 2k = 500g D =

A is 2100*(

B is 2100*(1

C is 2100*(2

Ding is 2100*(

4 x = 30%.

Multiply both sides by 4 at the same time

x=x=

4 x = 30%.

Multiply the two sides of the equal sign by 4 to get x=120%=

1. The volume of the cylinder and the cone are equal, which is the key.

2. Cylindrical volume (also conical volume): cubic centimeters).

3. The height of the cone: 3 square centimeters).

Volume new height * base area of the cone * (1 3) = volume.

New height = square centimeters.

As can be seen from the title, the volume of the cylinder and the cone are equal: the volume of the cylinder is the base area multiplied by the height The area of the cone is the base area multiplied by the height and divided by 3

It should be multiplied by the base area by the height in the division by 6.

Set, the price of the goods that can be bought is x and respectively.

dux+, because buying B can be better than buying Azhi

Buy two more, so the unit price of B DAO is x A is x+

Meaning from the inscription: 36 x-36 (x+.)

Solving this equation yields a weight of x=3

x+So the unit price of A is RMB per piece, and the unit price of B is RMB 3 per piece.

China's tax law stipulates that when personal income reaches a certain amount of data, it must be taxed, and the specific methods are as follows:

0-1600 yuan: no tax.

1600-2100 yuan: the part exceeding 1600 to 2100 yuan will be taxed at 5%.

2100-3600 yuan: the part exceeding 2100 to 3600 yuan will be taxed at 10%.

1) Wang Fang's mother's monthly salary is 2,500 yuan; How much is the actual salary of my mother after paying taxes every month?

2100-3600 yuan: the part exceeding 2100 to 3600 yuan will be taxed at 10%.

2500-2100) = 400 This part is taxed 400 * 10% = 40 yuan.

1600-2100 yuan: the part exceeding 1600 to 2100 yuan will be taxed at 5%.

This part is taxable (2100-1600) * 5% = 25 yuan.

Therefore, the total tax payment is 40 + 25 = 65 yuan.

The actual salary after paying tax every month is 2500-65=2435 yuan?

2) Dad's monthly salary is 3065 yuan after paying taxes, how much is Dad's monthly salary fixed amount?

Set: Wang Fang's father's monthly salary is X yuan.

x-(x-2100)*10%-(2100-1600)*5%=3065

Solve the equation to obtain: x=3200 yuan.

Or so: 3065>1600; The part of 1600 2100 is taxable: (2100-1600)*5%=25 yuan.

The part greater than 2100 and less than 3600 will be taxed at 10%, that is, this part will be taxed 1-10% = 90% after tax

Therefore, the pre-tax salary is (3065 + 25-2100) 90% + 2100 = 3200 yuan.

1) (2500-2100)*10%=40 yuan (2) Solution: Set the father's salary is x yuan. （x-2100）*10%+x=3065 x=2977

The teacher is 27 years old.

The number of years the teacher is older than the student is always the same.

If the teacher is x years older than the student, then:

1) When the student is 3 years old, the teacher is (3+x) years old; According to the title, the current age of the student is (3+x) years old;

2) When the teacher is 39 years old, the student is (39-x) years old; According to the title, the teacher's current age is (39-x) years;

3) Find the pattern: the current age of the student is (3+x); The teacher's current age is (39-x); We know that the number of years older than the student is always the same, and the teacher is always x years older than the student.

4) Knowing that the teacher is x years older than the student, the student's current age (3+x) is increased by x years, which should be equal to the teacher's current age (39-x);

Bulley equation: 3+x)+

x=（39-x）

Solution: x=12

Current age of the student: 3+x

Age of the teacher: 39-x

39-12=27 (years).