A certain zoo has 288 mammals, 25 percent of which are female. What pe

Question

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?

(1) 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.
(2) 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.

King407 · Answer

25% of 288 are female = 72 and Male = 216

=> Mb + Mnb = 216 and Fb + Fnb = 72 (b= born in zoo, nb = not born in zoo)

A) Mb = 3 Fnb ---  Insufficeint

B) Mnb = 3 Mb => 4Mb = 216 and Mb = 54 and Mnb = 162; Still no info about Females ---  Insufficeint

Combining A and B, we know Mnb, we can clearly find Fnb and hence Fb and will be able to calculate the %. So, No need to solve any further. --- ---  Sufficeint

Hence Answer is C

askhere · Answer

Answer is C.

See attached table. Let x be the number of female mammals not born at zoo.

Ambarish

Razween · Answer

But we dont no out for 288.. how many were born in zoo

PrepTap · Answer

Hi Razween,

From the information in the question:

Male (born at zoo) + Male (not born at zoo) = 75% of 288 = 216

Female (born at zoo) + Female (not born at zoo) = 25% of 288 = 72

Statement 1: 
Male (born at zoo) = 3 Female (not born at zoo)
Not sufficient

Statement 2: 
Male (not born at zoo) = 3 Male (born at zoo) 
=> 4 Male (born at zoo) = 216 
=> Male (born at zoo) = 216/4 = 54
As we have no information about the females. Not Sufficient

Statement 1 + Statement 2:
Male (born at zoo) = 3 Female (not born at zoo)
& Male (born at zoo) = 216/4 = 54
Hence, Female (not born at zoo) = 54/3 = 18

We Know:
Female (born at zoo) + Female (not born at zoo) = 25% of 288 = 72
Hence, Female (born at zoo) = 72 - Female (not born at zoo) = 72 - 18 = 54

Mammals born at zoo = Male (born at zoo) + Female (born at zoo) = 54 + 54 = 108
As we know the number of mammals born at zoo, we can find the percentage.
Sufficient.

Answer (C)

Best,
PrepTap

OptimusPrepJanielle · Answer

It might be more convenient to use the following variables to solve for the percentage:
Males born at zoo = a
Males not born at zoo = b
Females born at zoo = c
Females not born at zoo = d

The question is asking for (a+c)/(a+b+c+d)

We are given 
 a + b + c + d = 288
c + d = 72 (25 percent of 288)
a + b = 216 (solved by subtracting 72 from 288)

Statement 1: a=3d, or (a/3)=d; Not sufficient.
Statement 2: b=3a; Not sufficient.
this can be substituted into the equation a + b = 216
a + 3a = 216 => a = 54
54 + b = 216 => b = 162

But we still need to know the value of c.

(Statement 1 + Statement 2) Sufficient.
From statement two we solved for a and b. 
From statement one we can rewrite d in terms of a.
a=3d => (a/3)=d
From the original question you know that c+d = 72
so c + (a/3) = 72
We solved for a from Statement 2. c + (54/3) = 72 => c=54
(a+c)/(a+b+c+d) = (54+54)/288

C

bumpbot · Answer

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A certain zoo has 288 mammals, 25 percent of which are female. What pe

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