Question

Первая бригада может выполнить задание за 9 дней,а вторая - за 12 дней.Первая бригада работала над выполнением этого задания 3 дня потом вторая бригада работала закончив работу.За сколько дней было выполнено задание?

Answer 1

1:9=1\9
1:12=1\12
1\9+1\12=4\36+3\36=7\36
не знаю

Answer 2

Calculation of Task Completion Time

To determine the number of days it took to complete the task, we can use the concept of work rates. Let's denote the work rate of the first brigade as x (in units of work per day) and the work rate of the second brigade as y (in units of work per day).

According to the given information, the first brigade can complete the task in 9 days, and the second brigade can complete the task in 12 days.

We can set up the following equations based on the work rates and the time each brigade worked:

Equation 1: x * 3 = 1 (work done by the first brigade in 3 days is equal to 1 unit of work) Equation 2: y * t = 1 (work done by the second brigade in t days is equal to 1 unit of work)

To find the value of t, we need to solve these equations simultaneously.

Solving the Equations

From Equation 1, we can solve for x: x = 1/3 Substituting this value of x into Equation 2, we get: (1/3) * t = 1

Simplifying the equation, we find: t = 3 Therefore, it took the second brigade 3 days to complete the task.

Answer

The task was completed in a total of 6 days. The first brigade worked for 3 days, and then the second brigade worked for 3 days to finish the task.

Please note that the sources provided do not directly answer the given question. The solution is derived based on mathematical calculations and assumptions about work rates.

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