SOLUTION: Please double check my work Two marbles are drawn without replacement from a box with 3 white, 2 green, 2 red, and 1 blue marble. Find the probability. The first marble is whi

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Question 171639This question is from textbook
: Please double check my work
Two marbles are drawn without replacement from a box with 3 white, 2 green, 2 red, and 1 blue marble. Find the probability. The first marble is white and the second marble is blue.
p(white) = 3/8
p(green) = 2/8 = 1/4
p(red) = 2/8 = 1/4
p(blue) = 1/8
I came up with the answer of 6/8. Am I right? This question is from textbook

Answer by Earlsdon(6294) (Show Source):
You can put this solution on YOUR website!
This is a case of "sampling without replacement"
In this problem, you first find the probability that a white marble is drawn, expressed as . You have correctly found this to be .
Now, you need to find the probabilty that a blue marble was next drawn, given that a white marble was previously drawn. This is expressed as P(B|W) and, because there are now only 7 marbles (from an initial 8 marbles) in the bag, this would be expressed as: P(B|W) = 1/7.
Now you can find the probability that the first marble drawn (without replacement) was white and the second mable was blue:
P(W and B) = P(W)*P(B|W) = =