Question

Перша бригада робітників переплила 546 книжок за78 робочих годин. Друга бригада, працюючи разом із першою, можепереплисти таку саму кількість книжок за 42 години. За скільки годин друга бригада переплете 546 книжок, працюючи самостійно? Решить и сделать обернену задачу.

Answer 1

1)60:5=12(га)-1 бригада за 1 день. 2)60:(5+1)=10(га)-2 бригада за 1 день. 3)12+10=22(га)-1и2 бригада за 1день. 4)22*4=48(га)-1 и 2 бригада за 4 дня  Ответ:1 и 2 бригаду уберут 48га урожая.

Answer 2

Problem Analysis

We are given that the first team of workers took 78 hours to bind 546 books, and the second team, working together with the first team, took 42 hours to bind the same number of books. We need to determine how many hours the second team would take to bind 546 books working independently.

Solution

Let's assume that the second team can bind x books in one hour when working independently. We can set up the following equation based on the given information:

First team's work rate: 546 books / 78 hours = 7 books per hour

Combined work rate of both teams: 546 books / 42 hours = 13 books per hour

Second team's work rate when working with the first team: Combined work rate - First team's work rate = 13 books per hour - 7 books per hour = 6 books per hour

Now, we can set up another equation to find the work rate of the second team when working independently:

Second team's work rate when working independently: Combined work rate - First team's work rate = 6 books per hour

Simplifying the equation, we have:

x books per hour = 6 books per hour

Therefore, the second team can bind 6 books per hour when working independently.

To find the number of hours it would take for the second team to bind 546 books, we can set up the following equation:

546 books / x books per hour = number of hours

Substituting the value of x, we have:

546 books / 6 books per hour = number of hours

Simplifying the equation, we find:

Number of hours = 91 hours

Therefore, the second team would take 91 hours to bind 546 books when working independently.

Reverse Problem

To solve the reverse problem, we need to determine how many books the second team can bind in a given number of hours when working independently.

Let's assume that the second team can bind y books in one hour when working independently. We can set up the following equation:

y books per hour = 546 books / 91 hours

Simplifying the equation, we find:

y books per hour = 6 books per hour

Therefore, the second team can bind 6 books per hour when working independently.

To find the number of books the second team can bind in a given number of hours, we can set up the following equation:

y books per hour * number of hours = number of books

Substituting the value of y, we have:

6 books per hour * number of hours = number of books

Simplifying the equation, we find:

Number of books = 6 * number of hours

Therefore, the second team can bind 6 times the number of hours in books when working independently.

Please let me know if anything is unclear or if you need further assistance!