In a sample of college students, 40 percent are third year students an

Question

In a sample of college students, 40 percent are third year students and 70 percent are not second-year students. What fraction of those students who are not third-year students are second-year students?

(A) 3/4
(B) 2/3
(C) 4/7
(D) 1/2
(E) 3/7

(A) 3/4
(B) 2/3
(C) 4/7
(D) 1/2
(E) 3/7

thorinoakenshield · Accepted Answer

Hi,

I used the table method. Assume, there are 100 students in total. As you can see, 30/60 = 1/2, hence ANSWER: D

TO

ps_dahiya · Answer

D

First Year = F
Second Year = S
Third Year = T = 40

F + T = 70
So F = (F+T) - T = 70-40 = 30 and S = Total - (F+T) = 100 - 70 = 30

Not third year students = F + S = 30 + 30 = 60

Fraction = S/(F + S) = 30/60 = 1/2

krisrini · Answer

Let the number of students be 100.

3rd year = 40
First year or 3rd year = 70 => First year = 30
and Second year = 30
Second /First + Second = 30/60 = 1/2

amit2k9 · Answer

if the total sample is 100

then T T!

s 0 30 30

s! 40 30 70
 40 60 100

30/60 gives 1/2

ramprakash · Answer

Assume Total students = 100

3rd year students = 40 -- Frm the Question

So, 1st + 3rd + 4th year students = 70

2nd year students = 30

students who are not third year = 60

Fraction of 2nd years in those 60 sudents = 30/60 = 1/2.

subhashghosh · Answer

0.4S - 3rd yr students

0.7S - not 2nd yr students

0.6S - not 3rd yr students

0.3S - 2nd yr Students

=> 0.3S/0.6S = 1/2

Answer - D

pinkcupcake · Answer

Hi there! Here is the approach I took:

Third year students: 40% 
Not Third Year: 60%

Not Second Year: 70%
Second Year: 30%

What fraction of those students who are not third-year students are second-year students?

We know those who are not third year are 60% and we know second year students are 30%

30/60 simplifies to 1/2

Answer choice D

OptimusPrepJanielle · Answer

Since we're talking till third year students so we have first year, second year and third year students. Given that T = 40 ----- (I) F + T = 70 ----- (II) From (I) and (II), F = 30 Hence S = 100 - 40 - 30 = 30 Those who are not third year students = F + S = 30 + 30 = 60 Fraction of second year and those who are not third year students = 30/60 = 1/2 Hence option D -- Optimus Prep's GMAT On Demand course for only $299 covers all verbal and quant. concepts in detail. Visit the following link to get your 7 days free trial account: https://www.optimus-prep.com/gmat-on-demand-course

ScottTargetTestPrep · Answer

We can let the total number of students be 100. Since 40% are third-year students, 40 students are third-year. Thus, 60 students are not third-year. Since 70% are not second-year, 70 students are not second-year. Thus, 100 - 70 = 30 students are second-year.

Since 60 students are not third-year and 30 students are second-year, the fraction of students who are not third-year but are second-year is:

30/60 = 1/2

Answer: D

Andrewcoleman · Answer

I'm not sure this is right

KarishmaB · Answer

This is alright assuming a three year college course. It doesn't matter how many years there are. We have second year, third year and "rest of the years".

nikitathegreat · Answer

Why did you take third year and second year students as 0?

Paras96 · Answer

Let total no. of students be 100
Therefore, No. of third year students=40
No. of not second-year students=70
Therefore no. of 1st year students = No. of not second-year students - No. of third year students = 70-40=30
Therefore 
No. of 1st year students 30
No. of 2nd year students 30
No. of 3rd year students 40
Total no. of students 100
No. of not 3rd -year students 60

Therefore, No. of 2nd year students/No. of not 3rd -year students=30/60=1/2
Hence Answer is D

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