Out of a box that contains 4 black and 6 white mice, three are randomly chosen. What is the probability that all three will be black?
a) 8/125.
b) 1/30.
c) 2/5.
d) 1/720.
e) 3/10
OA is A
What is the MAthematecal approach to solve this? An Expert contribution is needed pls.
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You posted the same question 45 minutes ago (here: https://www.beatthegmat.com/probability-t299833.html)Roland2rule wrote:Out of a box that contains 4 black and 6 white mice, three are randomly chosen. What is the probability that all three will be black?
a) 8/125.
b) 1/30.
c) 2/5.
d) 1/720.
e) 3/10
OA is A
What is the MAthematecal approach to solve this? An Expert contribution is needed pls.
P(all 3 selected mice are black) = P(1st mouse is black AND 2nd mouse is black AND 3rd mouse is black)
= P(1st mouse is black) x P(2nd mouse is black) x P(3rd mouse is black)
= 4/10 x 3/9 x 2/8
= 1/30
= B
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Brent
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