Conditional Probability
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Example: in a class of 40 students, 25 take English and 10 take both English and Spanish. Picking a student who takes English at random, what is the chance they also take Spanish? Here A is “takes Spanish” and B is “takes English”. Change the values to work out your own case.
Step by step
What each term means
- Conditional Probability
- The probability of A happening given that B has already happened. It shows how the occurrence of B affects the probability of A.
- Probability of the Intersection
- The probability that both A and B happen. It is the overlap between events A and B.
- Probability of B
- The probability of event B. It normalizes the formula, keeping the conditional probability between 0 and 1.