Question

Из 180 студентов 30 не сжали экзамен.20не сдали курсовую работу,15 и то и другое. Пусть событие А студент сдал экзамен. В студент сдал курсовую работу.найти вероятность того что студент не сдал экзамен если известно что он не сдал курсовую работу

Answer 1

180 делим 100 и умножаем на 15 ответ 27 

Answer 2

Given Information:

- Total number of students: 180 - Number of students who did not pass the exam: 30 - Number of students who did not submit the coursework: 20 - Number of students who did not pass both the exam and coursework: 15

Calculation:

To find the probability that a student did not pass the exam given that they did not submit the coursework, we can use conditional probability.

Let's define the events: - A: Student passed the exam - B: Student submitted the coursework

We are given that 15 students did not pass both the exam and coursework. So, the number of students who did not pass the exam but submitted the coursework is 30 - 15 = 15.

The probability that a student did not pass the exam given that they did not submit the coursework can be calculated as follows:

P(A' | B) = P(A' ∩ B) / P(B)

Where: - P(A' | B) is the probability that a student did not pass the exam given that they did not submit the coursework. - P(A' ∩ B) is the probability that a student did not pass the exam and did not submit the coursework. - P(B) is the probability that a student did not submit the coursework.

We can calculate the probabilities as follows:

- P(A' ∩ B) = 15 / 180 = 1/12 - P(B) = 20 / 180 = 1/9

Substituting the values into the formula:

P(A' | B) = (1/12) / (1/9) = (1/12) * (9/1) = 9/12 = 3/4

Therefore, the probability that a student did not pass the exam given that they did not submit the coursework is 3/4.