Conditional probability
Conditional probability in simple terms is the probability of occurrence of an event given that another event has already occurred. It is given by the following formula:
P(B|A)= P(A and B)/P(A)
Here in this formula the values stand for:
|
Probability value |
Description |
|---|---|
|
P(B|A) |
This is the probability of occurrence of event B given that event A has already occurred. |
|
P(A and B) |
The probability that both event A and B occur. |
|
P(A) |
This is the probability of occurrence of an event A. |
Now let's try to understand this using an example. Suppose we have a set of seven figures as follows:
As seen in the preceding figure, we have three triangles and four rectangles. So if we randomly pull one figure from this set the probability that it belongs to either of the figures will be:
P(triangle) = Number of Triangles / Total number of figures = 3 / 7
P(rectangle) = Number of rectangles / Total number of figures = 4 / 7
Now suppose we break the figure into two individual sets...
