SOLUTION: tom takes 20 coins from a box, and he gets 12 red coins and 8 black coins. if the whole box contains 10000 coins, how many of them are black

Question 937679: tom takes 20 coins from a box, and he gets 12 red coins and 8 black coins. if the whole box contains 10000 coins, how many of them are black
Found 2 solutions by stanbon, ewatrrr:
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Tom takes 20 coins from a box, and he gets 12 red coins and 8 black coins. if the whole box contains 10000 coins, how many of them are black
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Based on empirical probability, p(black) = 8/20 = 2/5
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Your Problem::
# of black = (2/5)*10,000 = 4000
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Cheers,
Stan H.
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Answer by ewatrrr(24785) (Show Source): You can put this solution on YOUR website!
8/20 = 2/5
= 4000 are expected to be black
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