Question

Помогите пожалуйста!!!Двое рабочих , работая вместе , выполняют некоторую работу за х дней. Один рабочий выполняет всю работу за m дней, другой рабочий за n дней . Найдите х.

Answer 1

В день рабочий выполняет 1/m часть работы, второй 1/n если что / деление.
Вместе они выполняют 1/m+1/n=(m+n)/mn часть работы
(m+n)x/mn=1; x=mn/(m+n)

Answer 2

Ответ внизу на фото

Answer 3

Problem Analysis

We have two workers who are working together to complete a task. One worker can complete the task in m days, while the other worker can complete the task in n days. We need to find the number of days it will take for both workers to complete the task together.

Solution

To find the number of days it will take for both workers to complete the task together, we can use the concept of work rates. The work rate of a worker is defined as the amount of work they can complete in one day.

Let's assume that the work rate of the first worker is W1 and the work rate of the second worker is W2. We can calculate their work rates using the formula:

W1 = 1/m (work rate of the first worker)

W2 = 1/n (work rate of the second worker)

The total work rate when both workers are working together is the sum of their individual work rates:

Total work rate = W1 + W2

Since the total work rate is the amount of work that can be completed in one day when both workers are working together, we can calculate the number of days it will take to complete the task by dividing the total work to be done by the total work rate:

Number of days = 1 / (Total work rate)

Let's substitute the values of W1 and W2 into the equation to find the number of days it will take for both workers to complete the task together.

Calculation

Given that one worker can complete the task in m days and the other worker can complete the task in n days, we have:

W1 = 1/m

W2 = 1/n

The total work rate is the sum of their individual work rates:

Total work rate = W1 + W2

Substituting the values of W1 and W2:

Total work rate = 1/m + 1/n

The number of days it will take for both workers to complete the task together is:

Number of days = 1 / (Total work rate)

Substituting the value of the total work rate:

Number of days = 1 / (1/m + 1/n)

Simplifying the equation:

Number of days = mn / (m + n)

Therefore, the number of days it will take for both workers to complete the task together is mn / (m + n).

Answer

The number of days it will take for both workers to complete the task together is mn / (m + n).