Posted by the man on Sunday, May 20, 2012 at 2:15am.
One bag contains 4 white balls and 6 black balls. Another bag contains 8 white balls and 2 black balls. A coin tossed to select a bad, then a ball is randomly selected from that bag.
Suppose white ball was drawn. What is the probability that it came from the first bag?

MATH 12 HELP!  Reiny, Sunday, May 20, 2012 at 8:45am
Since a coin toss is used to select either bag1 or bag2
the prob that bag1 is choses is 1/2
prob that a white ball is choses from bag1 = 4/10 = 2/5
so prob of your 'event' = (1/2)(2/5) = 1/5 
MATH 12 HELP!  the man, Sunday, May 20, 2012 at 6:37pm
but the answer in my book says 1/3... Maybe its wrong?

MATH 12 HELP!  DOMICA, Friday, September 26, 2014 at 8:01am
PR=BROWN