# How is Bayes' Theorem used to solve complex probability questions?

##### 1 Answer

Aug 14, 2015

Using the ex-post probabilities, it tries to calculate ex-ante probability.

#### Explanation:

Suppose there are 3 production units A, B and C. They are used to produce Good-X. Again, the probabilities of a randomly selected item from A, B and C are known.

If we mixed up all their output. Now, if we select one item, we do not know from which production unit, it has come from.

O.K., Suppose the selected Item is defective, we can find out the probability about which production unit has produced it.