Question

Задание 2 (50 баллов). - В летний лагерь приехали три подруги: Маша, Катя и Полина. Известно, что каждая девочка имеет одну из следующих фамилий: Петрова, Семёнова и Сидорова. Маша не Сидорова. Мама Кати — врач. Катя учится в 5 классе. Сидорова учится в 4 классе. Мама Петровой — повар. Какая фамилия у Полины? Решите задачу с помощью таблицы. Покажите полное решение. Под таблицей запишите ход решения.​

Answer 1

Ответ:

Сидорова. Так как Катя в 5 классе, то есть её ячейка с классом занята, а Маша не Сидорова.

Answer 2

Problem Analysis

We are given the following information: - Three friends named Masha, Katya, and Polina have arrived at a summer camp. - Each girl has one of the following surnames: Petrova, Semyonova, or Sidorova. - Masha is not Sidorova. - Katya's mother is a doctor. - Katya is in the 5th grade. - Sidorova is in the 4th grade. - Petrova's mother is a cook.

We need to determine Polina's surname using a table and provide a step-by-step solution.

Solution

Let's create a table to organize the given information:

| Name | Surname | Mother's Occupation | Grade | |--------|-----------|---------------------|-------| | Masha | | | | | Katya | | | | | Polina | | | |

From the given information, we can fill in the following details: - Masha is not Sidorova, so she must be either Petrova or Semyonova. - Katya's mother is a doctor, so Katya cannot be Petrova. - Katya is in the 5th grade, so she must be Semyonova. - Sidorova is in the 4th grade, so Masha must be Petrova. - Petrova's mother is a cook.

Now we can fill in the table:

| Name | Surname | Mother's Occupation | Grade | |--------|-----------|---------------------|-------| | Masha | Petrova | Cook | | | Katya | Semyonova | Doctor | 5 | | Polina | | | |

Since Masha is Petrova and Katya is Semyonova, the only remaining surname for Polina is Sidorova.

Therefore, Polina's surname is Sidorova.

Step-by-Step Solution

1. Start with an empty table: | Name | Surname | Mother's Occupation | Grade | |--------|-----------|---------------------|-------| | Masha | | | | | Katya | | | | | Polina | | | |

2. From the given information, fill in the known details: - Masha is not Sidorova, so she must be either Petrova or Semyonova. - Katya's mother is a doctor, so Katya cannot be Petrova. - Katya is in the 5th grade, so she must be Semyonova. - Sidorova is in the 4th grade, so Masha must be Petrova. - Petrova's mother is a cook. | Name | Surname | Mother's Occupation | Grade | |--------|-----------|---------------------|-------| | Masha | Petrova | Cook | | | Katya | Semyonova | Doctor | 5 | | Polina | | | |

3. Determine Polina's surname: - Since Masha is Petrova and Katya is Semyonova, the only remaining surname for Polina is Sidorova. | Name | Surname | Mother's Occupation | Grade | |--------|-----------|---------------------|-------| | Masha | Petrova | Cook | | | Katya | Semyonova | Doctor | 5 | | Polina | Sidorova | | |

Therefore, Polina's surname is Sidorova.