Question 40310
<pre><font size = 3><b>Two urns contain each contain white balls and black balls. Urn 1 contains four
white balls and two black balls urn 2, contains six white balls and five black
balls. A ball is drawn from each urn. What is the probability that both balls
are black?

Urn 1 contains 6 balls, 2 of which are black, so the probability of drawing
a black ball from urn 1 is 2/6 or 1/3

Urn 2 contains 11 balls, 5 of which are black, so the probability of drawing
a black ball from urn 2 is 5/11

P(getting black ball from urn 1 AND getting black ball from urn 2) 

since these events are independent, we may multiply their probabilities

P(getting black ball from urn 1) × P(getting black ball from urn 2) =

1/3 × 5/11 = 5/33 

(or a little more than 15% of the time.)

Edwin
AnlytcPhil@aol.com</pre>