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GRE Prep Club Team Member
Joined: 20 Feb 2017
Posts: 2506
Given Kudos: 1055
GPA: 3.39
From a group of 21 astronauts that includes 12 people with previous ex
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14 Sep 2022, 07:09
14 Sep 2022, 07:09
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From a group of 21 astronauts that includes 12 people with previous experience in space flight, a 3-person crew is to be selected so that exactly one person in the crew has previous experience in space flight. How many different crews of this type are possible?
A. 432
B. 594
C. 864
D. 1,330
E. 7.980
A. 432
B. 594
C. 864
D. 1,330
E. 7.980
Re: From a group of 21 astronauts that includes 12 people with previous ex
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18 Sep 2022, 10:33
18 Sep 2022, 10:33
Expert Reply
\(C^1_{12}*C^2_9=12*36=432\), where \(C^1_{12}\) is ways to select 1 astronaut with previous experience out of 12 and \(C^2_9\) is ways to select 2 astronauts without experience out of 9 remaining astronauts (21-12=9).
Answer: A.
Answer: A.
gmatclubot
Re: From a group of 21 astronauts that includes 12 people with previous ex [#permalink]
18 Sep 2022, 10:33
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