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by pradeepkaushal9518 » Fri Oct 01, 2010 4:19 am
A certain zoo has 288 mammals, 25 percent of which are female. What percent of the mammals in the zoo were born at the zoo?

The number of male mammals that were born at the zoo is three times the number of female mammals who were not born at the zoo.
The number of male mammals that were not born at the zoo is three times the number of male mammals that were born at the zoo.
A Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D EACH statement ALONE is sufficient.
E Statements (1) and (2) TOGETHER are NOT sufficient.
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by shovan85 » Fri Oct 01, 2010 4:37 am
IMO C
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by shovan85 » Fri Oct 01, 2010 4:43 am
shovan85 wrote:IMO C
Say total Males = M and Females = F.
Born in zoo male M' and Born in zoo female = F'
not born in zoo M" and not Born in female F"

F = 72 and M = 216

1. M'=3F" (NS)
2. M" = 3M'
but M = 216
M"+M' = 216
4M' = 216 =>M' is found and so M" but we have no idea about how many females were born in zoo and how many were not.

Combining both 1 and 2 we can get total M'+F'. thus C
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by diebeatsthegmat » Sun Oct 03, 2010 8:02 pm
pradeepkaushal9518 wrote:A certain zoo has 288 mammals, 25 percent of which are female. What percent of the mammals in the zoo were born at the zoo?

The number of male mammals that were born at the zoo is three times the number of female mammals who were not born at the zoo.
The number of male mammals that were not born at the zoo is three times the number of male mammals that were born at the zoo.
A Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D EACH statement ALONE is sufficient.
E Statements (1) and (2) TOGETHER are NOT sufficient.
C too
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by Rahul@gurome » Sun Oct 03, 2010 8:49 pm
Solution:
The zoo has 288 mammals.
Number of female mammals is 25% * 288 = ¼ * 288 = 72.
Number of male mammals is 288 - 72 = 216.

Consider first (1) alone.
Let the number of female mammals who were not born at the zoo be x.
So the number of male mammals that were born at the zoo is 3x
Also the number of female mammals that were born at the zoo is 72 - x.
The number of male mammals who were not born at the zoo is 216 - 3x.
So number of mammals born at the zoo is 3x + 72 - x = 72 + 2x.
We need this value (72 + 2x)/288 * 100.
Since more information is required to get the above value, (1) alone is not sufficient.

Next consider (2) alone.
Let the number of male mammals born at the zoo be y.
So the number of male mammals not born at the zoo is 3y.
So at most what we get is y+3y = 216.
Or y = 54.
But we need more information regarding number of female mammals born or not born at the zoo to answer the question.
So (2) alone is not sufficient.

Next combine both the statements together and check.
On combining, we have that 3x = 54.
So x = 18.
So 72+2x = 108.
From this we can calculate the required % 108/288 * 100.

The correct answer is (C) .
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by Yanat » Tue Oct 05, 2010 9:02 am
In my view, the correct answer is C.

If we draw a grid we can solve this question easily.
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