Question

Ученики некоторого класса написали тест . Если бы каждый мальчик получил на 3 балла больше, то средний результат класса был бы на 1,2 балла выше, чем сейчас.Сколько процентов составляют в этом классе девочки?

Answer 1

1,2 / 3 * 100%=40% мальчиков

100% - 40% = 60% девочек

             Ответ: в классе 60% девочек

Answer 2

Calculation of the Percentage of Girls in the Class

To calculate the percentage of girls in the class, we need to use the information given in the question. Let's break down the problem step by step:

1. The average score of the class would be 1.2 points higher if each boy received 3 points more on the test. 2. We need to find the percentage of girls in the class.

Let's assume that there are a total of N students in the class, with B boys and G girls.

The current average score of the class can be calculated as follows: ``` Average score = (Total score of boys + Total score of girls) / Total number of students ```

If each boy received 3 points more, the new average score of the class would be: ``` New average score = (Total score of boys + 3B + Total score of girls) / Total number of students ```

According to the information given in the question, the new average score is 1.2 points higher than the current average score. Therefore, we can write the following equation: ``` New average score = Current average score + 1.2 ```

Substituting the equations for the average scores, we get: ``` (Total score of boys + 3B + Total score of girls) / Total number of students = (Total score of boys + Total score of girls) / Total number of students + 1.2 ```

Simplifying the equation, we have: ``` 3B / N = 1.2 ```

Solving for B, we find: ``` B = (1.2 * N) / 3 ```

Since we know that there are B boys in the class, we can calculate the number of girls as: ``` G = N - B ```

Finally, we can calculate the percentage of girls in the class as: ``` Percentage of girls = (G / N) * 100 ```

Let's calculate the percentage of girls using the given information.

Calculation:

From the given information, we know that if each boy received 3 points more, the new average score of the class would be 1.2 points higher than the current average score.

Using the equation derived above, we can calculate the percentage of girls in the class.

Let's assume that there are a total of 100 students in the class.

N = 100
B = (1.2 * N) / 3 = 40
G = N - B = 100 - 40 = 60
Percentage of girls = (G / N) * 100 = (60 / 100) * 100 = 60%

Therefore, in this class, the percentage of girls is 60%.

Please note that the above calculation is based on the assumption that there are 100 students in the class. If you have the actual number of students, you can substitute that value in the calculation to get the accurate percentage of girls in the class.

I hope this helps! Let me know if you have any further questions.