Pigs/ Cows

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Pigs/ Cows

by ruplun » Mon Jul 18, 2011 10:34 pm
Of the 60 animals on a certain farm, 2/3 are either pigs or cows.How many of the animals are cows?

(1) The farm has more than twice as many cows as it has pigs.
(2) The farm has more than 12 pigs.


I feel the ans to be A .Please confirm.

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by Anurag@Gurome » Mon Jul 18, 2011 10:44 pm
ruplun wrote:Of the 60 animals on a certain farm, 2/3 are either pigs or cows.How many of the animals are cows?

(1) The farm has more than twice as many cows as it has pigs.
(2) The farm has more than 12 pigs.


I feel the ans to be A .Please confirm.
Let total animals = T
cows = C and Pigs = P
Then (2/3) of 60 = P + C or P + C = 40

(1) C > 2P, It is NOT SUFFICIENT as there can be many possibilities.

(2) P > 12, It is NOT SUFFICIENT as there can be many possibilities.

Combining (1) and (2), If P = 13, then C > 26, so that P + C = 40
If P = 13, C = 27, then P + C = 40 (this is the only possibility)
If P = 14, then C > 28, if C = 29, then P + C = 43, not possible.
There are 27 cows. Hence, SUFFICIENT.

The correct answer is C.
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by ruplun » Mon Jul 18, 2011 11:16 pm
I beg to differ on the explanation ... 2/3 rd of the animals are cows or pigs ...then 2/3*60=40 are either cows or pigs

from (1) 3p=60
p=20, then no. of cows = 40
So A mist be sufficent.


The equation made by u 2/3 of 60 = pig + cow is wrong bcz its given either pigs or cows

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by Anurag@Gurome » Mon Jul 18, 2011 11:30 pm
ruplun wrote:I beg to differ on the explanation ... 2/3 rd of the animals are cows or pigs ...then 2/3*60=40 are either cows or pigs

from (1) 3p=60
p=20, then no. of cows = 40
So A mist be sufficent.

The equation made by u 2/3 of 60 = pig + cow is wrong bcz its given either pigs or cows
If the statement would have been "either 2/3 of the animals are pigs or they are cows", then your interpretation would be correct.
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by ruplun » Mon Jul 18, 2011 11:34 pm
ans is d