Q17 of 108 Page 271

Bag I contains 3 black and 2 white balls, Bag II contains 2 black and 4 white balls. A bag and a ball are selected at random. Determine the probability of selecting a black ball.

Given that


Bag I= [3Black, 2White], Bag II= [2 black, 4 white]


Let E1= event that bag I is selected


E2= event that bag II is selected


E3= event that a black ball is selected





∴P(E)= P(E1). P(E|E1) +P(E2). P(E|E2)







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