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# M04-04

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Math Expert
Joined: 02 Sep 2009
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16 Sep 2014, 00:22
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Difficulty:

25% (medium)

Question Stats:

73% (01:16) correct 27% (01:12) wrong based on 146 sessions

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What percent of the MIS students enrolled at Wisconsin University are female?

(1) 5% of female students at Wisconsin University are studying MIS.

(2) 12% of male students at Wisconsin University are studying MIS.

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16 Sep 2014, 00:22
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Official Solution:

We want to calculate $$\frac{MIS_{\text{female}}}{MIS_{\text{female}}+MIS_{\text{male}}}$$

(1) 5% of female students at Wisconsin University are studying MIS. If there are total of $$X$$ female students at Wisconsin University then $$0.05X=MIS_{\text{female}}$$. Not sufficient.

(2) 12% of male students at Wisconsin University are studying MIS. If there are total of $$Y$$ male students at Wisconsin University then $$0.12Y=MIS_{\text{male}}$$. Not sufficient.

(1)+(2) $$\frac{MIS_{\text{female}}}{MIS_{\text{female}}+MIS_{\text{male}}}=\frac{0.05X}{0.05X+0.12Y}$$, still not sufficient to calculate the desired ratio.

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01 Mar 2016, 08:02
Hi Bunuel,

could I not just come up with a total number of stundents in order to calculate from S1 the number of female MIS stundents and from S2 the number of male stundents so that I can afterwards calculate the precent of female students in the MIS class?

Where am I going wrong? I somehow always ended up with ~29%.

Best
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01 Mar 2016, 08:10
Erina89 wrote:
Hi Bunuel,

could I not just come up with a total number of stundents in order to calculate from S1 the number of female MIS stundents and from S2 the number of male stundents so that I can afterwards calculate the precent of female students in the MIS class?

Where am I going wrong? I somehow always ended up with ~29%.

Best

Let me try to answer. The issue with %ages in DS questions is that you will get different values for different total student number.

Case 1, lets say total students are = 100 ---> S1 gives females in MIS as 0.05*100 = 5

Case 2, lets say total students are = 200 ---> S1 gives females in MIS as 0.05*200 = 10

Thus, you get 2 different answers for the same question, what is %age (wrt total students) of females in MIS. This is the reason why S1 is not sufficient. Your approach would have worked for PS questions but for DS questions be wary of the percentages when the total number is not provided.

Hope this helps.
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16 Sep 2016, 05:40
since its percent I took 100 for example
where am I going wrong?
>> !!!

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16 Sep 2016, 09:14
paidlukkha wrote:
since its percent I took 100 for example
where am I going wrong?

We don't know whether the number of female students and male students are equal (100 and 100 in your matrix).
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06 Apr 2017, 22:17
Dear Bunnel,

I got confused and choose D (Both are sufficient).

Statement 1: Only 5% are females are studying MIS at W University then, 5% is the answer I concluded.
Statement 2: Same as above for males, so we can conclude females % from there.

Help me to correct the understanding of this question.

Thanks
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19 Sep 2017, 15:10
Hello,

Can we say that X+Y = 100% as all people are or male or female at MIS and so replace Y= 100-X in the equation you had with "both together"?

Kind regards,
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19 Sep 2017, 21:52
Tpral wrote:
Hello,

Can we say that X+Y = 100% as all people are or male or female at MIS and so replace Y= 100-X in the equation you had with "both together"?

Kind regards,

x and y in the solution are the number of males and females, not percentage, so you cannot say that x + y = 100.
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23 Oct 2017, 19:29
I think this is a poor-quality question and the explanation isn't clear enough, please elaborate. Why if the question is asking for a percentage of students, which is given by both 1 & 2, unable to be attained? Can you not give the amount of students on a 100% basis and thus derive a % of female students? A formal number of students is not given but is not needed as a percentage is given and the percentage of students will not change given a change in student numbers. The word "percent" in the question stem needs to be clarified.
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23 Nov 2017, 10:42
I think this is a poor-quality question and I don't agree with the explanation. Lets say "W" is the number of Wisconsin University students.

(1) MIS Females = 0.05W and (2) MIS Male = 0.12W

so (1) and (2) alone are not sufficient.

BUT, if we take both statement together we have :

%age of MIS Female = 0.05W / (0.05W+0.12W) = 0.05/0.17 ± 29.41%

So the W or the number of students at the university is not necessary to answer the question to me
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23 Nov 2017, 10:57
itsFanny wrote:
I think this is a poor-quality question and I don't agree with the explanation. Lets say "W" is the number of Wisconsin University students.

(1) MIS Females = 0.05W and (2) MIS Male = 0.12W

so (1) and (2) alone are not sufficient.

BUT, if we take both statement together we have :

%age of MIS Female = 0.05W / (0.05W+0.12W) = 0.05/0.17 ± 29.41%

So the W or the number of students at the university is not necessary to answer the question to me

You are wrong.

From (1): 5% of female students at Wisconsin University are studying MIS.

0.05(female students at Wisconsin University) = (female students studying MIS)

From (2): 12% of male students at Wisconsin University are studying MIS.

0.12(male students at Wisconsin University) = (male students studying MIS)/

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12 Apr 2018, 06:17
High Quality Question
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28 Aug 2018, 07:30
This question threw me off because I misread the statements. After reviewing multiple times, I finally understood it so I hope my explanation can help any others that are still confused why C is not the answer,

(1) 5% of female students at Wisconsin University are studying MIS.

(2) 12% of male students at Wisconsin University are studying MIS.

Example 1 Using C:
S1 means that 5% of the total number of female students at WU are studying MIS. But since we do not know the total number of female students at WU, let's plug in 100 as the total. That means there are 5 MIS female students.
S2 means that 12% of the total number of male students at WU are studying MIS. But since we do not know the total number of male students at WU, let's plug in 100 as the total. That means there are 12 MIS male students.
In summary, there are 17 MIS students and 200 total students at WU.

With the information above you get that there are 5/17 female MIS students =29%~

Example 2 Using C:
S1 means that 5% of the total number of female students at WU are studying MIS. But since we do not know the total number of female students at WU, let's plug in 100 as the total. That means there are 5 MIS female students.
S2 means that 12% of the total number of male students at WU are studying MIS. But since we do not know the total number of male students at WU, let's plug in 200 as the total. That means there are 24 MIS male students.
In summary, there are 29 MIS students and 300 total students at WU.

With the information above you get that there are 5/29 female MIS students = 17%~

***The answer is E because we do not know those totals. We can plug in anything we want to represent the total female or total male students studying at WU but based on what you plug in, you will get different answers. The totals between genders do not have to be equal either as it doesn't specify that it was a 1:1 ratio. ***
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07 Feb 2019, 22:33
Play on words, What percent of females in Wisconsin University vs What percent of MIS are females
Re: M04-04   [#permalink] 07 Feb 2019, 22:33
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# M04-04

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