A bag contains 6 purple marbles and 7 white marbles. Two marbles are drawn at random. One marble is drawn and not replaced. Then a second marble is drawn. What is the probability that the first marble is white and the second one is purple?
a) 1/12
b) 42/169
c) 7/26
d) 13/25

Question

A bag contains 6 purple marbles and 7 white marbles. Two marbles are drawn at random. One marble is drawn and not replaced. Then a second marble is drawn. What is the probability that the first marble is white and the second one is purple?
a) 1/12
b) 42/169
c) 7/26
d) 13/25

anonymous · Answer

Please! I need the help!

anonymous · Answer

This is what i think. 7/13 * 6/12 =7/26 but i am not 100% sure.

anonymous · Answer

I second ArcticStroke's reply.  You have 13 choices for the first marble and seven of them are white, so the chances of white on the first draw are 7/13.  Since you don't replace the first marble you have 12 choices for the second marble and 6 of them are purple, so you have a 6/12 chance of drawing a purple.  You then just need to multiply together to get the probability of drawing first white without replacement, then purple, which gives 7/26.

anonymous · Answer

Thanks to both of you!! I really needed the help in this one!