Question

There are two Bags, Bag I and Bag II. Bag I contains 4 white and 3 red balls while another Bag II contains 3 white and 7 red balls. One ball is drawn at random from one of the bags and it is found to be white. Find the probability that it was drawn from Bag I.

Answer 1

Let A, E₁, E₂ be the events defined as follow:
A : Ball drawn is white
E₁ : Bag I is chosen, E₂ : Bag II is chosen
Then we have to find P(E₁ / A)
Using Baye’s Theorem