Question

Масса тетрадки меньше массы книжки в 11.5 раз, среднее арифметическое этих двух величин равно 58 Найди массу тетрадки и массу книжки. Масса тетрадки равна : ? Масса книжки равна : ?​​

Answer 1

Среднее арифметическое чисел - это сумма всех чисел, делённая на их количество.

Пусть х - масса тетрадки, тогда 11,5х - масса книжки. Уравнение:

(х + 11,5х) : 2 = 58

12,5х = 58 · 2

12,5х = 116

х = 116 : 12,5

х = 9,28 (г) - масса тетрадки

11,5х = 11,5 · 9,28 = 106,72 (г) - масса книжки

Ответ: 9,28 г и 106,72 г.

Answer 2

Problem Analysis

We are given that the mass of a notebook is 11.5 times greater than the mass of a book. The average of these two masses is 58. We need to find the mass of the notebook and the mass of the book.

Solution

Let's assume the mass of the book is x. According to the given information, the mass of the notebook is 11.5 times greater than the mass of the book, so the mass of the notebook is 11.5x.

The average of the two masses is given as 58. We can calculate the average using the formula:

Average = (Sum of values) / (Number of values)

In this case, the sum of the two masses is x + 11.5x = 12.5x. Since we have two values (the mass of the book and the mass of the notebook), the average can be calculated as:

58 = (12.5x) / 2

To find the value of x, we can rearrange the equation:

12.5x = 58 * 2

12.5x = 116

x = 116 / 12.5

Now we can calculate the mass of the book (x) and the mass of the notebook (11.5x).

Calculation

Let's calculate the mass of the book and the mass of the notebook.

Mass of the book (x) = 116 / 12.5

Mass of the notebook (11.5x) = 11.5 * (116 / 12.5)

Answer

The mass of the book is approximately 9.28 units, and the mass of the notebook is approximately 106.72 units.

Please note that these values are approximate due to rounding.