. A bag contains 8 pink marbles, 5 green marbles and 10 brown marbles. What is the chance of drawing a brown marble? If a brown marble is drawn then placed back into the bag, and a second marble is drawn, what is the probability of drawing a pink marble? Give solutions exactly in reduced fraction form, separated by a comma.

Question

anonymous · Answer

How many brown marbles are there in the bag ??

mathmate · Answer

First draw:
10 brown marbles out of 23 total.  What is the probability?
Second draw:
situations have not changed from the first, and is considered independent.
After replacement of the brown marble, there are 8 pink marbles out of (still) 23 marbles.  What is the probability?

anonymous · Answer

10/23   8/23

mathmate · Answer

Excellent!  :)