A beg contains 4 red and 4 black , another bag contains 2 red and 6 black balls. One of the two bags is selected at random and a ball is drawn from the bag which is found to be red. Find the probability that the ball is drawn from the first bag.

Answer

`((1)/(2)xx(1)/(2))/((1)/(2)xx(1)/(2)xx(1)/(2)xx(1)/(4))=((1)/(4))/((1)/(4)xx(1)/(8))=((1)/(4))/((2+1)/(8))=((1)/(4))/((2+1)/(8))=((1)/(4))/((3)/(8))=(1)/(4)xx(8)/(3)=(2)/(3)`