The bag A contains 8 white and 7 black balls while the bag B contains 5 white and 4 black balls. One ball is randomly picked up from the bag A and mixed up with the balls in bag B. Then a ball is randomly drawn out from it. Find the probability that ball drawn is white.

Explanation

consider `E_{1}=A` black ball is put from bag `A` to `B`


`E_{2}=` A white ball is transferred from bag `A` to `B`


`A={A}` white ball is choosen



`therefore P(E_{1})=frac{7}{15} `


`P(E_{2})=frac{8}{15}`


`P(A / E_{1})=frac{5}{10}=frac{1}{2} `


`P(A / E_{2})=frac{6}{10}=frac{3}{5} `


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