- #1
mr_k
- 9
- 0
HI, sorry about the english
can you help me with this question?
box initially contains 10 black balls and 10 white balls. The following experiment is repeated indefinitely 20 times : A ball is drawn from the box; if the ball is black it is put back in the box, otherwise it is left out.
what is the probability to draw out all 10 white balls?
i need solve this with combinations.
i know that have (20 k) to draw K white balls and k<=10.hence Sample space :
http://img268.imageshack.us/img268/1744/lllfm.jpg
ו don't know to continue...
thanks!
can you help me with this question?
box initially contains 10 black balls and 10 white balls. The following experiment is repeated indefinitely 20 times : A ball is drawn from the box; if the ball is black it is put back in the box, otherwise it is left out.
what is the probability to draw out all 10 white balls?
i need solve this with combinations.
i know that have (20 k) to draw K white balls and k<=10.hence Sample space :
http://img268.imageshack.us/img268/1744/lllfm.jpg
ו don't know to continue...
thanks!
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