If a total of 84 students are enrolled in two sections of a calculus

Question

If a total of 84 students are enrolled in two sections of a calculus course, how many of the 84 students are female?

(1) 2/3 of the students in Section 1 are female.
(2) 1/2 of the students in Section 2 are male.

beattheheat · Answer

Statement 1: 2/3 of the students in Section 1 are female
We don't know the ratio of students in Section 2 and the ratio of students in each section -- Insufficient

Statement 2: 1/2 of the students in Section 2 are male
We don't know the ratio of students in Section 1 and the ratio of students in each section -- Insufficient

Combining 1&2: Still we don't know the ratio of students in each section.
Both Statement together are insufficient, Answer E

qw1981 · Answer

Looking at the question you will understand that the student are broken up into 2 sections I & II. Each section is further has male and Females. total students are 84. Hence Section I & II can have a combinations such as 10,74 1,73 42,42 etc.

S(1): Only ratio of m:f for section I. No way of determining exact value. Hence N.S

S(2): Only ratio of m:f for section II. No way of determining exact value. Hence N.S

Even after combining we do not know the ratio of students from section I & II to determine the various values. Hence N.S

THus answer is E.

anupamadw · Answer

Let there be x students in section-1 and y students in section-2
so, x+y=84

stmnt-1
2/3 of x = Female
we dont know how many female are from section-2
Insuff

stmnt-2
1/2 of y = male
1/2 of y= female
Insuff

from 1+2
2x/3+y/2 are total no.f female
still insuff
hence E

syamen · Answer

Let X be the number of students in Section-1 and Y be the number of students in Section-2. Then X+Y = 84. Need to find no of girls in two sections.

St-1 is not sufficient as we do not have any details of section - 2
St-2 is not sufficient as we do not have any details of section - 1

1 + 2 --> 2X/3 + Y/2 = ? Not sufficient. So Ans - E

g106 · Answer

From Statement 1: we know that 2/3 of the student are female, but we dont know the total of section 1 (Total could be 3 or 81)- Not sufficient
Statement 2: 1/ are female, again We don't know the total - Not sufficient

Ans E

eddyki · Answer

FEMALE + MALE = 84
CLASS A + CLASS B = 84 (?)

so (1) is not sufficient
and (2) is not sufficient 
-> no details about the other course

How about both:

CLASS A = 2/3a + 1/3a
CLASS B = 1/2b + 1/2b = 84 - CLASS A

we dont know about a or b..

together not sufficient -> E

shakticnb · Answer

Let there be x students in section-1 and y students in section-2
so, x+y=84

stmnt-1
2/3 of x = Female
we dont know how many female are from section-2
Insuff

stmnt-2
1/2 of y = male
1/2 of y= female
Insuff

from 1+2
2x/3+y/2 are total no.f female
still insSUFICENT CORRECT ANSWER E

rhine29388 · Answer

we need to find how many female students are there
statement 1 gives ratio of female to male students in section 1 is 2:1 clearly insufficient
Statement 2 gives ratio of male to female students in section 2 is 1 :1 clearly insufficient
combining both we don't get the ratio or division of students between 2 sections so again insufficient
Correct answer - E

anniaustin · Answer

let x = section 1, therfore no. of students in section 2 = 84-x
Combining (1) and (2) 
2x/3 + 1/2(84-x0 = no. of female
, so no. of female students = x/2 + 42

Still depends on the split per section. So we cannot tell from this information what is the no. of female students.

IMO E

Kimberly77 · Answer

Great explanation  syamen . One question for each statement, when 2/3 of the students in Section 1 are female, does it not mean/imply 1/3 of the students in Section 1 are male? Same with statement 2. Therefore combined statements make it C ? could you kindly clarify? thanks.

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If a total of 84 students are enrolled in two sections of a calculus

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