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a bag contains 4 white and 3 black balls.2 balls are drawn one at a time, randomly in succession.what is the probability that both the balls drawn out are white in color,if the first ball is not replaced after the first draw?
(A)9/49 (B)3/7 (C)2/7 (D)4/7 (E)16/49

Read Solution (Total 2)

fav case for 1st ball=4/7
fav cases for 2nd ball=3/6=1/2
so overall prob=4/7*(1/2)=2/7
14 years agoHelpfull: Yes(15) No(0)

2/7
14 years agoHelpfull: Yes(5) No(3)

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