In a study conducted on several schools in Phoenix, though the assignm

Question

In a study conducted on several schools in Phoenix, though the assignments did not require them to show the rough work, students of various classes sometimes showed the rough work on the assignments before submitting them to their teachers and sometimes did not. Marks on the rough work assignments were on average four percentage points higher than the marks on assignments without the rough work. Therefore, if the students regularly showed the rough work on the assignments, their average marks on the assignments would be significantly higher than it otherwise would have been.

Which of the following is an assumption on which the argument relies?

A. The marking system in the various schools follow the same pattern of giving marks.

B. The teachers give the extra marks to students for the extra effort the student makes even if the student has got the rough work incorrect.

C. Most teachers were inclined to give better grades to students who had shown the rough work than to the ones who had not.

D. If teachers regularly see the rough work done on the assignments, they will not go back to their original marking system.

E. Both the teachers who are strict in giving marks and who are lenient will be similarly influenced by the rough work on the assignments.

prince11goyal · Answer

I marked C as my answer. Not so convinced with D because there is no mention of a marking system (or we have to assume something about a marking system)

Daspodu · Answer

D does not make sense. C is better imo

Posted from my mobile device

SohGMAT2020 · Answer

Official Solution by GMATwhz:
Step 1 – Analysing the stimulus and question stem
The stimulus

In a study conducted on several schools in Phoenix, though the assignments did not require them to show the rough work, students of various classes sometimes showed the rough work on the assignments before submitting them to their teachers and sometimes did not.

This sentence presents a the details of a study
 o Students sometimes showed rough work on the assignments before they submitted it and sometimes did not.

o The assignments actually did not require the students to show the rough work.

Marks on the rough work assignments were on average four percentage points higher than the marks on assignments without the rough work.

This sentence presents the findings of the study
 o The assignments that had the rough work shown on them got on average 4 %age points more compared to the non- rough work assignments.

Therefore, if the students regularly showed the rough work on the assignments, their average marks on the assignments would be significantly higher than it otherwise would have been.

The conclusion drawn on the basis of the outcome of the study:
 o Conclusion: The average marks on the assignments will be significantly higher if the students regularly showed the rough work than when they did not.

Step 2 – Pre-thinking
1. Per the study, when students sometimes showed the rough work, they got on average, more marks.

2. And based on this the author concludes that if what the students did “sometimes” was done “all the time”, then the average marks would be significantly higher.

a. The missing link: Thus, the author thinks what happened sometimes will happen all the time in a similar manner.

b. What if the teachers got so used to seeing the rough work all the time that they stopped according any novelty to it?

i. In that case, the teachers could stop giving more marks and just give the marks that they were giving when the rough work was not there. After all the assignment does not ask the students to show the rough work.

1. Assumption: The teachers will not stop giving more marks if the rough work is shown regularly.

A. The marking system in the various schools follow the same pattern of giving marks.

Option A Feedback:
The passage says the “average marks” will go up. Thus, even if different schools follow different ways of giving marks, the increase in marks will be relative to the base marks. This choice is out of scope.

Incorrect Choice.

B. The teachers give the extra marks to students for the extra effort the student makes even if the student has got the rough work incorrect.

Option B Feedback:
This choice tells us the reason behind teachers giving more marks to students showing rough work. This supports the idea that it is the rough work that is causing the increase in average marks. However, there could be multiple reasons for teachers giving more marks to assignments with the rough work. Perhaps the teacher finds the rough work t be impressive. Thus, the reason behind the increase in marks does not matter.

Incorrect Choice.

C. Most teachers were inclined to give better grades to students who had shown the rough work than to the ones who had not.

Option C Feedback:
Most teachers could refer to more than 50% and even all. Is it necessary that “most” teachers should have given more marks to rough work assignments? No.

Even if less than 50% of teachers gave better grades, then also “average marks” could go up. Thus, this choice is a distortion & half-truth trap.

Incorrect Choice.

D. If teachers regularly see the rough work done on the assignments, they will not go back to their original marking system.

Correct Option
Option D Feedback:
This is in line with our pre-thinking.

Correct Choice.

E. Both the teachers who are strict in giving marks and who are lenient will be similarly influenced by the rough work on the assignments.

Option E Feedback:
This choice does not specify what “similarly influenced” means. Will they give more marks or less or the same? We also do not know how many teachers mark leniently and how many strictly. Thus, this choice has no impact on the conclusion.

This choice is out of scope.

Incorrect Choice.

tinbq · Answer

To be honest, I don't find the explanation why choice B is incorrect is persuasive. It's would be nice if further explanation is provided.

jingzhao8902 · Answer

I don't think that the person who write the question and answers have thought the logical relationship through. I agree with the above, C seems to be a better answer. Moreover, B has a similar argument as c as well. I think the correct answer should be either B or C. There isn't a strong link between the teachers give higher marks to students who write rough work and the original marking system, hence D would be an out of scope answer.

ravigupta2912 · Answer

I do agree with the above post that there is not a strong link between "rough work" and "original marking system" and hence option D is not very strong. However, that said, B is also weak since it just assumes the "rough work" to be a reason for "better grades" i.e. correlation with causation. My reasoning for eliminating B is below:-
=======================
B. The teachers give the extra marks to students for the extra effort the student makes even if the student has got the rough work incorrect. -- We don't know if that is the reason for extra marks. Maybe the pool of students who did the rough work also got more answers right? This is not the assumption on which the argument depends. If you negate this

"the teacher DOES NOT gives the extra mark to students for the extra effort... incorrect" - Does that weaken the conclusion? Yes. But only if we assume that extra marks are the reason for more marks. What if there are more reasons? Lets keep this still.
=======================

Need an expert opinion here.

Raman109 · Answer

Understanding the argument - (Option B and D language in the original question is different from the one in this prompt, so I have updated it to the original language)
In a study conducted on several schools in Phoenix, though the assignments did not require them to show the rough work, students of various classes sometimes showed the rough work on the assignments before submitting them to their teachers and sometimes did not. - Fact. 
Marks on the rough work assignments were on average four percentage points higher than the marks on assignments without the rough work. - Fact. So far, it's a correlation. We haven't been told about any cause yet. 
Therefore, if the students regularly showed the rough work on the assignments, their average marks on the assignments would be significantly higher than it otherwise would have been. - Conclusion. This straightaway converts the correlation to causation.

Option Elimination - Assumption

A. The marking system in the various schools follow the same pattern of giving marks. - Even if they use the different patterns the "average" mentioned in the conclusion can still go up. Out of scope.

B. The teachers give extra marks to students regardless of whether the student has done rough work. - Weakener.

C. Most teachers were inclined to give better grades to students who had shown the rough work than to the ones who had not. - Most can be any number between 51% and 100%. We need a bit more airtight.

D. If teachers regularly see the rough work done on the assignments, they will not go back to giving less marks as before. - Negate this. "If teachers regularly see the rough work done on the assignments, they will go back to giving less marks as before." This shatters the conclusion. Ok.

E. Both the teachers who are strict in giving marks and who are lenient will be similarly influenced by the rough work on the assignments. - "Similarly influenced " doesn't define less, more, or the same marks. We also don't know how many teachers are lenient or not. Out of scope.

saynchalk · Answer

The wording of option C makes the sentence have 2 possible meanings:
1. The teacher favored students that presented any for of rough work
2. The teacher favored the individual students that presented the rough work first

Because of the possibility of it considering something completely different from the rough work, I chose D

VerbalBot · Answer

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In a study conducted on several schools in Phoenix, though the assignm

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