Question

В классе было несколько учеников. После того как в класс вошли 7 учеников, а 3 ученика вышли из класса,в классе осталось 12 учеников. Сколько учеников было в классе сначала? Решить с помощью уровнения

Answer 1

Пусть было х учеников
сотавим уравнение
х+7-3=12
х+4=12
х=12-4
х=8 учеников было в классе

Answer 2

Problem Analysis

We are given the information that initially there were several students in the class. After 7 students entered the class and 3 students left, there were 12 students remaining in the class. We need to determine the initial number of students in the class.

Solution

Let's assume the initial number of students in the class is x.

According to the given information: - 7 students entered the class, so the number of students increased by 7. - 3 students left the class, so the number of students decreased by 3. - After these changes, there were 12 students remaining in the class.

We can express this information in the form of an equation:

x + 7 - 3 = 12

Simplifying the equation:

x + 4 = 12

Subtracting 4 from both sides of the equation:

x = 12 - 4

Simplifying further:

x = 8

Therefore, the initial number of students in the class was 8.

Answer

The initial number of students in the class was 8.