Percents

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Percents

by BTGmoderatorRO » Sun Dec 24, 2017 8:29 am
Anthony and Michael sit on the six member board of directors for company X. If the board is to be split up into 2 three-person subcommittees, what percent of all the possible subcommittees that include Michael also include Anthony?

(A) 20%
(B) 30%
(C) 40%
(D) 50%
(E) 60%

OA is C
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Percents

by Brent@GMATPrepNow » Sun Dec 24, 2017 8:33 am
Roland2rule wrote:Anthony and Michael sit on the six member board of directors for company X. If the board is to be split up into 2 three-person subcommittees, what percent of all the possible subcommittees that include Michael also include Anthony?

(A) 20%
(B) 30%
(C) 40%
(D) 50%
(E) 60%
Let's assume that we're creating subcommittees.
We want to place 6 people in the following spaces:
_ _ _ | _ _ _

First, we place Michael in one subcommittee; it makes no difference which one:
M _ _ | _ _ _

Now place Anthony.
We can see that there are 5 spaces remaining. 2 spaces are on the same subcommittee as Michael.
So the probability that they are on the same subcommittee is 2/5 = 40%
In other words, 40% of the possible outcomes feature Anthony and Michael on the SAME committee
Answer:C

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Brent
Brent Hanneson - Creator of GMATPrepNow.com
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