Bayes Theorem

Given :-

Step 1: Use Bayes' Theorem.
Use Bayes' Theorem to calculate the probability. Bayes' Theorem states that:
Step 2: Conclusion.
The probability that the red ball came from box is . Final Answer:

In a box,
and Also, given that,

Three vertices can be selected in ways.
The only equilateral triangles possible are
and

Let be the event that urn contains white balls and let B be the event that two white balls have been drawn then we have to find .
Since the four events and are equally likely
we have
is probability of event that the urn contains 2 white balls and both have been drawn.

Similarly


By Baye?s theorem,