There are 4 people and 4 marbles (3 white and 1 black) . Each take one marbles. What is the chance that the ball first person takes is black, the second person takes is black... .

Answer 1

Are these all separate events?

prob(first person takes black, others take white):
BWWW

= (1/4)(3/3)(2/2)(1/1) = 1/4

The others would be the same,
note that all cases would have to add up to 1, they do.

Answer 2

Then p(second person takes black)= 3/4* 1/3* 2/2*1/1=1/4

Answer 3

How can i draw this situation?

Answer 4

You answer of 3/4* 1/3* 2/2*1/1 = 1/4 , show this situation
WBWW

Answer 5

So was that correct? Do you know how can i draw this in a probability tree?