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WeeG
02-15-2010, 09:21 AM
There are 9 people in group A, 4 people in group B and 2 people in group C.
6 of them will win a ticket.

1. what is the probability that all the people from group B will win a ticket ?
2. what is the probability that all the people who won a ticket come from the same group ?

I want to verify my answers...

1. (4C4 * 11C2) / 15C6

2. (9C6 * 4C0 * 2C0 ) / 15C6

where aCb is the binomial coefficient ( a on b ).

thanks !

fed1
02-15-2010, 12:29 PM
looks good to me:eek: