Question

Двое очистили 400 штук картофеля. Один очищал 3 штуки в минуту, другой 2 штуки в минуту. Второй работал на 25 минут больше первого. Сколько времени работал каждый?

Answer 1

Составим и решим уравнение
Пусть первый работал х времени, тогда другой х+25. Значит:
3x+2(x+25)=400
3x+2x+50=400 - распределительное свойство
5x+50=400
5x=400-50
5x=350
x=350:5
x=70
Значит первый работал 70 минут, тогда второй x+25=70+25=95 минут
Ответ: 70 минут, 95 минут

Answer 2

Problem Analysis

Two people are tasked with peeling 400 potatoes. One person can peel 3 potatoes per minute, while the other can peel 2 potatoes per minute. The second person works for 25 minutes longer than the first person. We need to determine how long each person worked.

Solution

Let's assume that the first person worked for x minutes. Since the second person worked for 25 minutes longer, they worked for x + 25 minutes.

The first person peeled 3 potatoes per minute, so they peeled a total of 3x potatoes. The second person peeled 2 potatoes per minute, so they peeled a total of 2(x + 25) potatoes.

Since the total number of potatoes peeled by both people is 400, we can set up the following equation:

3x + 2(x + 25) = 400

Now, let's solve this equation to find the values of x and x + 25.

Calculation

Expanding the equation: 3x + 2x + 50 = 400

Combining like terms: 5x + 50 = 400

Subtracting 50 from both sides: 5x = 350

Dividing both sides by 5: x = 70

So, the first person worked for 70 minutes, and the second person worked for 70 + 25 = 95 minutes.

Answer

The first person worked for 70 minutes, and the second person worked for 95 minutes.