A survey recently conducted at the Global Business School has thrown

Question

A survey recently conducted at the Global Business School has thrown up two interesting findings.

Finding 1: In the last ten years, students attending Professor James’ Economics classes were more likely to score in the top 10% of the class than were other students

Finding 2: In the last ten years, most of the students who scored in the top 10% of the class did not take classes from Professor James.

If the statements above are true, which of the following must be true?

A) The quality of classes conducted by Professor James has probably decreased

B) The number of students not taking classes from Professor James has increased over the last ten years

C) There must be some factor other than attending Professor James’ classes that can also make a student perform well in the subject

D) The overall quality of the students who have joined Global Business School in the last ten years has increased

E) Professor James needs to change his teaching methods if he wants more students to attend his classes

KarishmaB · Accepted Answer

The first thing to do is to establish how the two findings co-exist.

Say there are10 professors with 100 students each. So 10% of total 1000 students would be the top 100 students. 
Say 20% of James' students make it to top 100 i.e. 20 of his students.
Of the other 9 professors, the students have a lower probability of making to top 100.

But of the top 100, 20 students are James' and 80 students are non-James'. So most of the top 10% did not come from James.

So there is something else that makes students successful (the 80 students who are not from James' class)

A) The quality of classes conducted by Professor James has probably decreased

Note that we have no data comparing 10 years back to today. So anything that says "this decreased over 10 yrs" or "that increased over 10 yrs" is not correct. We are only talking about the 10 year data - what has been happening for the last 10 years. Not what increased/decreased 10 yrs ago to now.

B) The number of students not taking classes from Professor James has increased over the last ten years

Same logic as (A)

C) There must be some factor other than attending Professor James’ classes that can also make a student perform well in the subject

Correct. The 80 students did succeed without James' class.

D) The overall quality of the students who have joined Global Business School in the last ten years has increased

Same logic as (A)

E) Professor James needs to change his teaching methods if he wants more students to attend his classes

This is a conjecture. What he needs to do to make more people attend his classes is beyond the scope of the argument.

Answer (C)

KaranB1 · Answer

C

This is an inference question. Because of the wording of the two findings it may appear that they
are contradictory in nature but this does not have to be so because finding 1 only talks about the
likelihood of a student doing well. It never states that students attending Professor James’
Economics classes were the only ones scoring in the top 10% of the class. So there could be other
students as well who were scoring in the top 10% of the class and who had not taken classes from
Professor James. Thus (C) can clearly be inferred from this as there must have been some other
reason (other than Professor James’ classes) for the excellent performance of these other students.

A. From the information in the argument, no inference can be made about the quality of classes

B. Again this may or may not have been the case but does not necessarily have to be the case

C. The correct answer

D. It is possible that the quality has remained constant or has even decreased in that the students
outside the top 10% are probably doing much better than were earlier students.

E. No such inference can be arrived at from the information in the stimulus

NinetyFour · Answer

My reasoning if it helps anyone:

Imagine if we have 100 students in the program.

Professor James teaches 10% of these students (10 total). If 40% of his students made the top 10% of the program overall than that means 4 students made it.

The second finding tells us that the majority of the top 10% of overall students (10 students) did not attend Professor James class. If 4 students made it from Professor James class, then 6 students did not attend his class.

As we can see both findings can be correct. For the other professors teaching, perhaps only 5% of their class made the top 10% of students. Professor James is 50%, even though his total students are still the minority in the overall class's top 10%.

A) Not necessarily

B) It could have, but it also could have decreased or stayed the same.

C) Absolutely true. Since there are 6 students that did not attend Professor James class than there must be something else that contributed to their success.

D/E) Irrelevant

VerbalBot · Answer

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A survey recently conducted at the Global Business School has thrown

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