amitbharadwaj7 wrote:
egmat wrote:
Hi all,
I think pretty interesting discussion has gone in this thread, with some of the members making really elaborate and explanatory posts.
However, I think the issue at hand can be simplified further. So, let me try my bit at it.
Clearly, the only confusion is between option C and option E. The only difference between option C and option E is that option E makes the entering year later than 1990.
So, let's just focus on this part:
Let's see the relevant part of the passage:
"In the Business program at a university, all candidates for the MBA in International Business who entered the program after 1990 took a seminar on Microeconomics"
and the relevant part of question stem
"If a student in the Business program described above took a seminar on Microeconomics"
So, the passage says that all students (or candidates, let's use the same terms) who entered program after 1990 took Microeconomics
Now consider, if I, during my MBA, took a course on Microeconomics; can you say that I entered the program only after 1990?
If your answer to this question is yes, then my question is that what makes you think that I could not have entered before 1990? Clearly, all students who entered after 1990 had to take Microeconomics but it doesn't mean that students who entered before 1990 could not take Microeconomics.
If students who entered before 1990 could indeed take Microeconomics, then I could be one of those students. Isn't it?
Let's consider an analogy here:
All students who entered the school in a red dress got a tight slap on their face.
Now, if I say that I got a tight slap on my face, can you say that I wore a red dress to the school?
No, you can't say that. Because a red dress ensures a slap but the school authorities could, at their whims and fancies, slap anyone in any dress
We are only given that a person in red dress won't be spared but we can't say about others.
Similarly, if a person took Microeconomics (a slap), we can't say he entered after 1990 (wore a red dress).
Hope this helps
If anyone has doubts, please feel free to ask.
Thanks,
Chiranjeev
Dear Chiranjeev;
I am a
E-Gmat Student. I appreciate the way you have explained the above example. I still have a doubt in this question. Student joining prior to 1990 can have both option to attend either seminar on MicroEconomics or Applied Economics. hence a student may have attended applied economics also if he is joining prior to 1990. The question asks which "must be true". Choice E is the condition which is must be true as it satisfies the required conditions in all cases.
Your justification for choice C is acceptable, but it is not always true, whereas choice E is always true.
Please explain and give one condition where E is not the choice for "must be true"
Many Thanks in Advance.
Regards,
Amit
I'll reiterate Chiranjeev's explanation with an example.
This is Conditional Logic. If X happens, Y happens.
Consider a simpler condition: If it is cold, I will wear a sweater.
The inverse of this statement is the negation of both clauses: If it is not cold, I will not wear a sweater.
The converse reverses the order of the clauses: If I wear a sweater, it is cold.
The contrapositive both negates and reverses: If I will not wear a sweater, it is not cold.
Under the rules of classical logic, if a statement is true, its contrapositive must also be true. The statement’s negation and converse, however, are NOT necessarily true. For the sweater example, this means the following:
Statement -> If it is cold, I will wear a sweater. TRUE
Inverse -> If it is not cold, I will not wear a sweater. TRUE OR FALSE – I may wear a sweater even if it is not cold.
Converse -> If I will wear a sweater, it is cold. TRUE OR FALSE. I may wear a sweater even if it is warm.
Contrapositive -> If I will not wear a sweater, it is not cold. TRUE. If it were cold, I would wear a sweater. Since I won’t wear a sweater, it must not be cold.
Initially, I was also tied between C & E. Then, I read the above logic and it has helped solving "Must be True" Q's correctly till date.
Let's come back to the Question.
Argument:
Condition 1 => In the Business program at a university, all candidates for the MBA in International Business who entered the program after 1990 took a seminar on Microeconomics, and
Condition 2 => All candidates for the MBA in International Business who entered the program after 1994 took a seminar on Applied Economics.
Contrapositive of Condition 2 => If a student did not attend a seminar on Applied Economics, then he must not have entered after 1994.
TRUEConverse of Condition 1 => If a students attends a seminar on Microeconomics, then he must have entered after 1990.
FALSENow C & E both contains the Contrapositive logic but NOTE E contains some additional info which is CONVERSE of Condition 1.
E : If the student was a candidate for the MBA in International Business, then the student entered the program
after 1990 and prior to 1995.
Hence, E may be TRUE OR FALSE. The words are confusing but once you practice using this logic, it'll become easy. Hope it helps.
This is the original link
https://www.knewton.com/blog/gmat/2010/12/01/how-to-use-formal-logic-gmat-critical-reasoning/