Q6 of 12 Page 13

A bag X contains 4 while balls and 2 black balls, while another bag Y contains 3 white balls and 3 black balls. Two balls are drawn (without replacement) at random from one of the bags and were found to be one white and one black. Find the probability that the balls were drawn from bag Y.

OR


A and B throw a pair of dice alternately, till one of them gets a total of 10 and wins the game. Find their respective probabilities of winning, if A starts first.[CBSE 2016]

Given,


Bag X = 4 white, 2 black


Bag Y = 3 white ,3 black


Let A be the event of selecting one white and one black ball


E1 = first bag selected


E2 = second bag selected


P(E1) = p(E2) =


⇒


⇒


⇒


⇒


⇒


⇒


OR


Probabilities(win) =


Probablities(lose) =


⇒


⇒


By using the formula of infinite G.P.


⇒

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