In a class 3/4th of the students had not prepared for the test. Of the

Question

In a class 3/4th of the students had not prepared for the test. Of the students who had prepared for the test, 2/3rd passed the test. If only 25 percent of the class passed the test, what fraction of the students who had not prepared for the test, failed the test?

A. 1/12
B. 1/9
C. 1/2
D. 2/3
E. 8/9

A. 1/12
B. 1/9
C. 1/2
D. 2/3
E. 8/9

GMATWhizTeam · Accepted Answer

Solution 
 • Let us assume that the total 12 students are there in the class.
 https://www.dropbox.com/s/zs87om0sl1g1sib/tree.jpg?dl=1 
• So, fraction of the students who hadn't prepared for the test and failed  = \frac{8}{9}  
Thus, the correct answer is  Option E.

NitishJain · Answer

IMO E

Ley y = did not prepare and passed

from the figure: x/6 + y = x/4
y = x/12

Not Prepared and not passed =3x/4 - x/12 =2x/3 = 8/9 (3x/4)
 = (8/9)th of students who did not prepared

ScottTargetTestPrep · Answer

Solution:

If we let the number of students = 120, then 90 did not prepare for the test and 30 did. Also, of the students who prepared, 30 x 2/3 = 20 passed the test, and 1/4 x 120 = 30 total students passed the test. Thus, 30 - 20 = 10 students who passed the test actually had not prepared for it. Since 90 students did not prepare for the test, 90 - 10 = 80 of these unprepared students failed the test. Therefore, the fraction of the students who had not prepared for the test, failed the test, is 80/90 = 8/9.

Answer: E

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