Question

учитель разложил весь мел в 2 коробки в отношении 7:4. Когда из большой коробки взяли 12 кусков мела, мела в коробках стало поровну. сколько всего кусков мела было первоначально?

Answer 1

7-4=3части - равны 12 кускам

12/3=4куска одна часть

7*4=28кусков в одной коробке

4*4=16кусков во второй

28+16=44куска всего

Answer 2

Пусть х кусков мела в одной части, тогда в большей коробке 7х кусков, а в меньшей -- 4х кусков мела. По условию задачи сост уравнение:

7х-12=4х

7х-4х=12

3х=12

х=4 куска в одной части

7*4=28 кусков мела в большей коробке

4*4=16 кусков мела в меньшей коробке

 

28+16=44 куска мела всего

Answer 3

Problem Analysis

The problem states that a teacher divided all the chalk into two boxes in a ratio of 7:4. When 12 pieces of chalk were taken from the larger box, the number of chalk pieces in both boxes became equal. The task is to determine the total number of chalk pieces initially.

Solution

Let's assume the initial number of chalk pieces in the larger box is 7x and in the smaller box is 4x, where x is a positive integer.

According to the problem, when 12 pieces of chalk were taken from the larger box, the number of chalk pieces in both boxes became equal. This can be expressed as:

7x - 12 = 4x + 12

To solve this equation, we can isolate x on one side:

7x - 4x = 12 + 12

Simplifying the equation:

3x = 24

Dividing both sides by 3:

x = 8

Now that we have the value of x, we can find the total number of chalk pieces initially:

Total number of chalk pieces = Number of chalk pieces in the larger box + Number of chalk pieces in the smaller box = 7x + 4x = 7 * 8 + 4 * 8 = 56 + 32 = 88

Therefore, the total number of chalk pieces initially was 88.

Answer

The total number of chalk pieces initially was 88.