Date Page
7.
a
A bag contains 6 black and 7 white
marbles of same shape and size two
marbles are drawn randomly on offer
another without replacement show the
probabilities of all possible outcomes
a tree diagrams.
​

the probabilities are just

6/13 * 5/12 for two black marbles

6/13 * 7/12 for a black marble first, white second

7/13 * 6/12 for a white marble first, black second

7/13 * 6/12 for two white marbles

the 13 is just the summ of all marbles and the 12 is when we alrdy took one out of the bag. 5, 6 and 7 are the current numbers of marbles of some color respectively