Question

5) В танцевальном ансамбле 31 школьник. Известно , что 15 из них - брюнеты или брюнетки , 10 девочек - блондинки , 6 мальчиков - шатены , девочек больше , чем мальчиков , но брюнеток меньше , чем брюнетов. Сколько в ансамбле брюнетов , если каждый мальчик - брюнет или шатен , а каждая девочка - брюнетка или блондинка? ВАРИАНТЫ ОТВЕТОВ: А)7, Б)8, В)9, Г) Ответ отличен от приведенных

Answer 1

7+10=17 девочек 8+6=14 мальчиков

Answer 2

Problem Analysis

We are given the following information about a dance ensemble: - There are 31 schoolchildren in the ensemble. - 15 of them are brunettes. - 10 of the girls are blondes. - 6 of the boys are light-haired. - There are more girls than boys. - There are fewer brunettes than boys.

We need to determine the number of brunettes in the ensemble.

Solution

Let's analyze the given information step by step to find the number of brunettes in the ensemble.

1. We know that there are 31 schoolchildren in the ensemble. 2. We also know that there are more girls than boys, but we don't have the exact numbers. 3. We are given that 15 of the schoolchildren are brunettes. 4. We are also given that 10 of the girls are blondes. 5. Additionally, we know that 6 of the boys are light-haired.

To find the number of brunettes, we need to determine the number of boys and girls in the ensemble.

Let's assume the number of boys is "b" and the number of girls is "g."

From the given information, we can form the following equations:

Equation 1: b + g = 31 (since the total number of schoolchildren is 31) Equation 2: g > b (since there are more girls than boys) Equation 3: 15 = b + g - 10 (since there are 15 brunettes, and 10 of them are girls)

Simplifying Equation 3, we get: Equation 4: b + g = 25

Now, we have two equations with two variables (Equations 1 and 4). We can solve them simultaneously to find the values of "b" and "g."

Subtracting Equation 4 from Equation 1, we get: (b + g) - (b + g) = 31 - 25 0 = 6

This means that the equations are inconsistent, and there is no unique solution. It is not possible to determine the exact number of brunettes in the ensemble based on the given information.

Therefore, the answer is Г) Ответ отличен от приведенных (The answer is different from the options provided).

Please let me know if you need any further assistance.