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

Probability that both balls are white
`=(6)/(117) =0.051=5.1\%`

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
`=(2)/(2+7) =(2)/(9)`

Probability of drawing white ball from second urn
`=(3)/(3+10) =(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
`= (2)/(9) * (3)/(13)=(6)/(117) =0.051=5.1\%`