SOLUTION: A box contains 25% black balls and 75% white balls. The same number of black balls as were in the box are added (so new number of black balls is twice the original number). A ball

Question 619850: A box contains 25% black balls and 75% white balls. The same number of black balls as were in the box are added (so new number of black balls is twice the original number). A ball is now drawn from the box at random. What is the probability that it is black?
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
A box contains 25% black balls and 75% white balls. The same number of black balls as were in the box are added (so new number of black balls is twice the original number). A ball is now drawn from the box at random. What is the probability that it is black?
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Converting the problem to numbers:
Original mix: 25 black and 75 white.
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New mix: 50 black and 75 white
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P(black) = 50/125 = 2/5 = 40%
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Cheers,
Stan H.
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