Question

Учитель разложил весь имеющийся мел в две коробки в отношении 7:4. Когда из первой коробки израсходовали 12 кусков , то мела в коробках стало поровну. Сколько всего кусков мела было у учителя первоночально ?

Answer 1

7-4 = 3(ч)
12:3=4(к)-мела на одну часть.
4*7=28(к)- мела в 1 коробке.
4*4=16(к)-мела во 2 коробке.
28+16=44

Answer 2

Problem Analysis

The teacher divided all the chalk available into two boxes in a ratio of 7:4. When 12 pieces were taken out of the first box, the number of chalks in the boxes became equal. We need to find the total number of chalks the teacher initially had.

Solution

Let's assume the total number of chalks the teacher initially had is x.

According to the given information: - The first box had 7/11 of the total chalks initially. - The second box had 4/11 of the total chalks initially.

When 12 pieces were taken out of the first box, the number of chalks in both boxes became equal. This means that the second box had 12 fewer chalks than the first box.

Using this information, we can set up the following equation:

(7/11)x - 12 = (4/11)x

To solve for x, we can multiply both sides of the equation by 11 to eliminate the denominators:

7x - 132 = 4x

Now, we can solve for x:

7x - 4x = 132

3x = 132

x = 44

Therefore, the teacher initially had a total of 44 chalks.

Answer

The teacher initially had a total of 44 chalks.