Two urns each contain green balls and blue balls. Urn I contains 4 green balls and 6 blue balls, and Urn II contains 6 green balls and 2 blue balls. A ball is drawn at random from each urn. What is the probability that both balls are blue?

Question

anonymous · Answer

there are 6 out of 10 blue balls in the first urn. so probability of drawing blue ball from that is 6/10 or 3/5
there are 2 out of 8 blue balls in the second urn. so probability of drawing a blue ball from that is 2/8 or 1/4. 
to get the probability of drawing BOTH blue balls. multiply 3/5 x 1/4

anonymous · Answer

just tell me if something isn't clear =)

anonymous · Answer

okay, I get where the 6/10 and 2/8 are coming from but where's the 3/5 and 1/4 coming from?

anonymous · Answer

3/5 is simplfiied version of 6/10
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1/4 is simplified version of 2/8
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