Question

Боря, Витя, Гриша и Егор встретились на Всероссийской олимпиаде по информатике. Ребята приехали из разных городов: Москвы, Омска, Санкт-Петербурга и Кирова. Известно, что Боря жил в одной комнате с мальчиком из Кирова и ни один из этих дыух мальчиков никогда небыл ни в Москве, ни в Санкт-Петербурге. Гриша играл в одной команде с мальчиком из Москвы, а вечерами к ним заходил приятель из Кирова. Егор и мальчик из Москвы увлекались игрой в шахматы. Кто из ребят откуда приехал?

Answer 1

Боря из Омска, Витя из Москвы, Гриша из Санкт-Петербурга, Егор из Кирова

Answer 2

Explanation of the Problem

The problem provides information about four boys—Borya, Vitya, Grisha, and Egor—who met at the All-Russian Olympiad in Informatics. The boys came from different cities: Moscow, Omsk, St. Petersburg, and Kirov. There are also details about their living arrangements and interactions with boys from other cities.

Solution

Based on the given information, we can deduce the following: - Borya lived in the same room as a boy from Kirov. - Neither of these two boys had ever been to Moscow or St. Petersburg. - Grisha was on the same team as a boy from Moscow, and in the evenings, a friend from Kirov visited them. - Egor and the boy from Moscow were interested in playing chess.

Deductions

1. Borya: Since Borya lived with a boy from Kirov, and neither of them had been to Moscow or St. Petersburg, it can be inferred that Borya is from Kirov. - Source: 2. Grisha: Grisha was on the same team as a boy from Moscow and had a friend from Kirov who visited them in the evenings. Therefore, Grisha is from Omsk. - Source: 3. Egor: Egor and the boy from Moscow were interested in playing chess. Hence, Egor is from St. Petersburg. - Source: 4. Vitya: By process of elimination, Vitya is from Moscow. - Source: Therefore, the boys are from the following cities: - Borya: Kirov - Grisha: Omsk - Egor: St. Petersburg - Vitya: Moscow