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PS combinations,manhattan

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PS combinations,manhattan

by ukr.net » Mon Dec 10, 2007 10:14 am
There are 7 executives, including CEO & CFO, that are asked to form a task force of 5 members. However, CEO & CFO may not both be assigned to the task force. Given this, how many ways are there to form the task force among the 7 executives?
6
10
11
21
28
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by sujaysolanki » Mon Dec 10, 2007 10:56 am
is it 7C5 =21 ... thnks for the correction
Last edited by sujaysolanki on Tue Dec 11, 2007 9:20 pm, edited 1 time in total.
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by gmatguy16 » Mon Dec 10, 2007 3:01 pm
7c5 is not correct since cfo and ceo both are not possible..
imo 5 c 4 * 2 (1 of either cfo /ceo since both are not possible and 4 out of 5) or 5 c 5 = 11
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by patrik.herzog » Tue Dec 11, 2007 8:11 am
The correct answer is 11.

13456
13457
13467
13567
14567

23456
23457
23467
23567
24567

34567

(The numbers 1-7 represent the 7 execs, where 1 is the CEO and 2 the CFO.)

From my point of view the easiest way to solve this question is to write down all possible solutions.
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PS

by ukr.net » Tue Dec 11, 2007 10:24 am
The correct ANS is 11.
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