Question

В классе девочек в два раза больше,чем мальчиков. Если из этого класса уйдут три девочки и придут три мальчика, то девочек и мальчиков станет поровну. Сколько учеников в данном классе? Помогите плис!!!

Answer 1

Х - количество мальчиков
2х - количество девочек
х+3=2х-3
х=6 - количество мальчиков
2*6=12=количество девочек
12+6=18 детей в классе

Answer 2

Problem Analysis

We are given that there are twice as many girls as boys in a class. If three girls leave and three boys join, the number of girls and boys will be equal. We need to determine the total number of students in the class.

Solution

Let's assume the number of boys in the class is x. Since there are twice as many girls as boys, the number of girls in the class is 2x.

When three girls leave, the number of girls becomes 2x - 3. Similarly, when three boys join, the number of boys becomes x + 3.

According to the given information, when the number of girls and boys becomes equal, we have the equation:

2x - 3 = x + 3

To solve this equation, we can subtract x from both sides:

2x - x - 3 = x - x + 3

Simplifying, we get:

x - 3 = 3

Adding 3 to both sides, we have:

x - 3 + 3 = 3 + 3

Simplifying further, we get:

x = 6

Therefore, the number of boys in the class is 6. Since there are twice as many girls as boys, the number of girls is 2 * 6 = 12.

The total number of students in the class is the sum of the number of boys and girls:

Total number of students = Number of boys + Number of girls = 6 + 12 = 18

So, there are 18 students in the class.

Answer

There are 18 students in the given class.