Question

Two urns contain white balls and yellow balls. The first urn contains 2 white balls and 7 yellow balls and the second urn contains 3 white balls and 10 yellow balls. A ball is drawn at random from each urn. What is the probability that both balls are white?
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Answer 1

-- The first urn has 9 balls in it all together, and 2 of them are white.
If you don't peek, then the prob of pulling out a white ball is  2/9 .

-- The second urn has 13 balls in it all together, and 3 of them are white.
If you don't peek, then the prob of pulling out a white ball is  3/13 .

-- The probability of being successful BOTH times is

        (2/9) x (3/13)  =  ( 6/117 )  =  about  0.0513  or  5.13% (rounded) 

Answer 2

Answer:

Probability that both balls are white $=\frac{6}{117} =0.051=5.1\%$

Step-by-step explanation:

Probability is the ratio of number of favorable outcomes to total number of outcomes.

The first urn contains 2 white balls and 7 yellow balls and the second urn contains 3 white balls and 10 yellow balls.

Probability of drawing white ball from first urn $=\frac{2}{2+7} =\frac{2}{9}$

Probability of drawing white ball from second urn $=\frac{3}{3+10} =\frac{3}{13}$    

Probability that both balls are white = Probability of drawing white ball from first urn x  Probability of drawing white ball from second urn

Probability that both balls are white $= \frac{2}{9} \times \frac{3}{13}=\frac{6}{117} =0.051=5.1\%$