SOLUTION: 1. An urn contains 15 marbles – 8 blue, 5 red, and 2 white. If 2 marbles are chosen without replacement, find the probability that the first marble is blue and the second is white.

Algebra ->  Probability-and-statistics -> SOLUTION: 1. An urn contains 15 marbles – 8 blue, 5 red, and 2 white. If 2 marbles are chosen without replacement, find the probability that the first marble is blue and the second is white.      Log On


   

Question 352205: 1. An urn contains 15 marbles – 8 blue, 5 red, and 2 white. If 2 marbles are chosen without replacement, find the probability that the first marble is blue and the second is white.
2. A quick quiz consists of a true/false question followed by a multiple-choice question with four possible answers (a,b,c,d). An unprepared student makes random guesses for both answers. What is the probability that s/he gets both answers correct?

Found 2 solutions by Fombitz, jim_thompson5910:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!

1.P%28B%29=8%2F15
P%28W%29=2%2F14=1%2F7
P=P%28B%29%2AP%28W%29=%288%2F15%29%281%2F7%29=8%2F105
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2. First question correct:P=1%2F4
Second question correct:P=1%2F4
Two questions correctP=%281%2F4%29%281%2F4%29=1%2F16

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
2) P(both answers correct) = (1/2)*(1/4) = 1/8