Question

В турнире по шашкам участвуют 25 спортсменов,из них 7 - из России, в том числе Илья Боков.Порядок,в котором шашисты играют друг с другом, определяются жребием.Найдите вероятность того,что в первом туре Илья Боков будет играть с шашистом из России.При необходимости ответ округлите до сотых.

Answer 1

1) 25-1=24 участника за исключением Ильи Бокова
2) 7-1=6 участников из России без Ильи
3) Р=6/24=0,25 вероятность того, что в первом туре Илья Боков будет играть с шашистом из России

Ответ 0,25

Answer 2

Probability of Ilya Bokov playing against a Russian chess player in the first round

To find the probability of Ilya Bokov playing against a Russian chess player in the first round, we need to consider the total number of possible matchups and the number of favorable outcomes.

Given that there are 25 participants in the tournament, including 7 from Russia, we can calculate the total number of possible matchups in the first round using the combination formula:

Total number of possible matchups = C(25, 2) = 25! / (2! * (25-2)!) = 300

Now, let's calculate the number of favorable outcomes, which is the number of ways Ilya Bokov can be paired with a Russian chess player. Since there are 7 Russian chess players, the number of favorable outcomes is:

Number of favorable outcomes = C(7, 1) = 7! / (1! * (7-1)!) = 7

Finally, we can calculate the probability by dividing the number of favorable outcomes by the total number of possible matchups:

Probability = Number of favorable outcomes / Total number of possible matchups = 7 / 300 ≈ 0.0233

Therefore, the probability that Ilya Bokov will play against a Russian chess player in the first round is approximately 0.0233 (rounded to the nearest hundredth).