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Ch. 3 - Probability
Larson - Elementary Statistics: Picturing the World 8th Edition
Larson8th EditionElementary Statistics: Picturing the WorldISBN: 9780137493470당신이 사용하는 게 아니라요?교과서 변경
3장, 문제 3.2.35

"According to Bayes’ Theorem, the probability of event A , given that event B has occurred, is
P(A|B) = P(A) * P(B|A)P(A) * P(B|A) + P(A') * P(B|A').
In Exercises 33–38, use Bayes’ Theorem to find P(A|B).
35. P(A) = 0.25, P(A') = 0.75, P(B|A) = 0.3 , and P(B|A') = 0.5 "

검증된 단계별 안내
1
Step 1: Recall Bayes' Theorem formula: P(A|B) = (P(A) * P(B|A)) / (P(A) * P(B|A) + P(A') * P(B|A')). This formula helps calculate the conditional probability of event A given that event B has occurred.
Step 2: Identify the given values from the problem: P(A) = 0.25, P(A') = 0.75, P(B|A) = 0.3, and P(B|A') = 0.5.
Step 3: Substitute the given values into the numerator of the formula: P(A) * P(B|A) = 0.25 * 0.3.
Step 4: Substitute the given values into the denominator of the formula: P(A) * P(B|A) + P(A') * P(B|A') = (0.25 * 0.3) + (0.75 * 0.5).
Step 5: Simplify the numerator and denominator expressions separately, then divide the numerator by the denominator to find P(A|B).

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
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주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Bayes' Theorem

Bayes' Theorem is a fundamental principle in probability theory that describes how to update the probability of a hypothesis based on new evidence. It states that the probability of event A given event B (P(A|B)) can be calculated using the formula P(A|B) = P(A) * P(B|A) / (P(A) * P(B|A) + P(A') * P(B|A')). This theorem is particularly useful in scenarios where prior knowledge about the events is available.
추천 영상:
05:10
Bayes' Theorem

Conditional Probability

Conditional probability is the measure of the probability of an event occurring given that another event has already occurred. It is denoted as P(A|B), which represents the probability of event A occurring under the condition that event B is true. Understanding conditional probability is crucial for applying Bayes' Theorem, as it allows us to assess how the occurrence of one event influences the likelihood of another.
추천 영상:
03:53
Conditional Probability Rule

Prior and Posterior Probabilities

In the context of Bayes' Theorem, prior probability refers to the initial assessment of the likelihood of an event before new evidence is considered (P(A)), while posterior probability is the updated probability after taking into account the new evidence (P(A|B)). The distinction between these two types of probabilities is essential for understanding how new information can change our beliefs about the likelihood of events.
추천 영상:
5:37
Introduction to Probability