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Juaz
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Caas
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Bluebird
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Caas
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Bluebird, you are right
Solving this way you get 6/7

I still vote for E :)
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Himalayan
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Himalayan
Juaz
In a room filled with 7 people, 4 ppl have exactly 1 friend in room and 3 ppl have exactly 2 friends in room (Assuming that friendship is a mutual relationship). If 2 individuals are selected from the room at random, what is the probability that those 2 individuals are not friends.

A. 5/21
B. 3/7
C. 4/7
D. 5/7
E. 16/21

= 1- 3c2/7c2 = 5/7


wow.. that was oversighting...
seems E.

= 1 - (1 + 1 +3c2)/7c2 = 16/21
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apache
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friends set x=(1,2) y=(3,4) z=(5,6,7)

1,2,3,4 - each has one friend
(5,6,7) each has two freinds
now to select 2 persons who are not friends
1 from x ,1 from y = 2*2
1 from x ,1 from z = 2*3
1 from y ,1 from z = 2*3

so p=16/7C2 = 16/21

whats the OA
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grad_mba
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Ditto as Apache did.

In terms of formula -

(3c1.4c1)/7c2 + (2c1.2c1)/7c2 = 16/21
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Juaz
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OA is 16/21. Thanks guys!



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