Last visit was: 20 Jun 2025, 15:53 It is currently 20 Jun 2025, 15:53
Close
GMAT Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Close
Request Expert Reply
Confirm Cancel
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 20 June 2025
Posts: 102,214
Own Kudos:
Given Kudos: 93,961
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 102,214
Kudos: 734,015
 [28]
5
Kudos
Add Kudos
23
Bookmarks
Bookmark this Post
Most Helpful Reply
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 20 June 2025
Posts: 102,214
Own Kudos:
734,015
 [6]
Given Kudos: 93,961
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 102,214
Kudos: 734,015
 [6]
3
Kudos
Add Kudos
3
Bookmarks
Bookmark this Post
User avatar
hassi01
Joined: 31 Jul 2022
Last visit: 24 Jun 2023
Posts: 11
Own Kudos:
15
 [5]
Given Kudos: 12
Posts: 11
Kudos: 15
 [5]
5
Kudos
Add Kudos
Bookmarks
Bookmark this Post
General Discussion
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 20 June 2025
Posts: 102,214
Own Kudos:
Given Kudos: 93,961
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 102,214
Kudos: 734,015
Kudos
Add Kudos
Bookmarks
Bookmark this Post
The question or/and solution has been revised and edited. Thank you sayantanc2k !!!
User avatar
Rickooreo
Joined: 24 Dec 2021
Last visit: 15 Feb 2023
Posts: 305
Own Kudos:
30
 [1]
Given Kudos: 240
Location: India
Concentration: Finance, General Management
GMAT 1: 690 Q48 V35
GPA: 3.95
WE:Real Estate (Consulting)
GMAT 1: 690 Q48 V35
Posts: 305
Kudos: 30
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
KarishmaB gmatophobia sayantanc2k

Can you please help me understand why option D is wrong.
Option D - Many of the electricians who passed had completed a course in electronics covering some of the topics also included in the syllabus of the certification exam.

D basically says that many of the electricians who passed completed a course covering similar material to the ones asked in the exam. Shouldn't completing the course mean that those electricians did indeed studied more hours?
User avatar
gmatophobia
User avatar
Quant Chat Moderator
Joined: 22 Dec 2016
Last visit: 20 Jun 2025
Posts: 3,142
Own Kudos:
8,760
 [2]
Given Kudos: 1,860
Location: India
Concentration: Strategy, Leadership
Posts: 3,142
Kudos: 8,760
 [2]
2
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Rickooreo
KarishmaB gmatophobia sayantanc2k

Can you please help me understand why option D is wrong.
Option D - Many of the electricians who passed had completed a course in electronics covering some of the topics also included in the syllabus of the certification exam.

D basically says that many of the electricians who passed completed a course covering similar material to the ones asked in the exam. Shouldn't completing the course mean that those electricians did indeed studied more hours?

While experts weigh in their opinion, sharing my two cents -

The conclusion of the argument is - more hours one studies, the more likely he is to pass.. So the magazine / author believes that extras hours that the electricians put was the only reason and there was no other variable(s) at play.

We have to strengthen the argument. So in someway, we have to lend support to the conclusion in the line of assumption made.

Option D - infact weakens as it presents us with an alternate reason, that might have been at play and helped the electricians pass the advanced certification exam. That is the option presents us with a reason that goes against the conclusion that the result was not because of more number of hours that the electricians had put in but because of the familiarity of the material that the electricians had.

Now, I understand your thoughts are around the fact, that the electricians might have put some additional hours as a part of the initial course work, but that's something we are concocting to support our hypothesis. It's not given in the passage, so its not right to assume one. The electricians might have cheated in the course work and have genuinely put in more hours to pass the advance certification exam. :dontknow:

In CR one should stick to the details given in the passage.

Reminds me of a statement GMATNinja always emphasis in his CR sessions- "Is it their words or my words"

Clearly in here it is my words if I assume that merely because the electricians have taken an additional course, that means they have put in more efforts studying for that course.

Hope that helps.
User avatar
KarishmaB
Joined: 16 Oct 2010
Last visit: 20 Jun 2025
Posts: 16,059
Own Kudos:
73,819
 [2]
Given Kudos: 472
Location: Pune, India
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 16,059
Kudos: 73,819
 [2]
1
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
Bunuel
Electrician Magazine surveyed 1,000 electricians who took an advanced certification exam. Of these 1,000 candidates 500 passed the exam and 500 failed. The magazine asked the electricians how many hours they had studied for the exam. It was found that those who passed had studied on average 50 hours, and those who failed had studied on average 20 hours. The magazine concluded that the more hours one studies, the more likely he is to pass.

Which of the following, if true, would most strengthen the conclusion of the magazine?


A. Some of the electricians in the survey actually studied more than 100 hours.
B. Many of those surveyed thought the exam was unnecessary and did not reflect on their ability as electricians.
C. The electricians in the survey all took the exam shortly after reaching five years of experience as an electrician.
D. Many of the electricians who passed had completed a course in electronics covering some of the topics also included in the syllabus of the certification exam.
E. Majority of the electricians who failed had college degrees in a variety of fields not related to electrical subjects.

1000 people took an exam. 500 passed. 500 failed.
It was found that the 500 who passed had studied on avg 50 hrs while 500 who failed had studied on avg 20 hrs.

Conclusion: The more hours you put in, the more likely you are to pass.

We need to strengthen this. Note that there could be many reasons why the 500 who passed actually did pass. We only checked for one characteristic and that was the number of hours they put in. What if the 500 who passed had an avg experience of 10 yrs compared with an avg experience of 2 yrs of those who did not pass? What if the 500 who passed had already acquired some related certifications and hence knew the material much better? What if the 500 who passed had college degrees in the field of Electricals? Any one of these could be the differentiating factor. We only checked for one factor (number of hrs) and concluded based on that. We can strengthen that number of hours was responsible by showing that other possible factors were not responsible.

C. The electricians in the survey all took the exam shortly after reaching five years of experience as an electrician.
Option (C) says that they had the same experience. So it says that a difference in their experience level was not responsible. So it increases the likelihood that 'number of hrs put in' was the factor responsible. Note that it just increases the probability but that is all we need from a strengthener - an increased probability.

A. Some of the electricians in the survey actually studied more than 100 hours.

We are talking about averages in our argument. Even if some people studied a lot (we don't know whether they passed or failed), it doesn't impact our conclusion.

B. Many of those surveyed thought the exam was unnecessary and did not reflect on their ability as electricians.

What they thought about the importance of the exam is irrelevant.

D. Many of the electricians who passed had completed a course in electronics covering some of the topics also included in the syllabus of the certification exam.

If anything, it weakens the conclusion. It links 'passing' with another factor - 'other courses in electronics.' But it doesn't tell us that those who failed had not completed such courses so the information is limited. In any case, we can be sure that it doesn't strengthen.

E. Majority of the electricians who failed had college degrees in a variety of fields not related to electrical subjects.

Same as option (D). If anything, it weakens the conclusion. It links 'failing' with another factor - non electrical degree. But it doesn't say that those who passed had electrical degrees. But in any case, we know that it doesn't strengthen.

Answer (C)
User avatar
SSgmat2024
Joined: 02 Sep 2024
Last visit: 24 Jan 2025
Posts: 1
Posts: 1
Kudos: 0
Kudos
Add Kudos
Bookmarks
Bookmark this Post
I think this the explanation isn't clear enough, please elaborate.
User avatar
bb
User avatar
Founder
Joined: 04 Dec 2002
Last visit: 20 June 2025
Posts: 40,951
Own Kudos:
Given Kudos: 22,664
Location: United States (WA)
GMAT 1: 750 Q49 V42
GPA: 3
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
GMAT 1: 750 Q49 V42
Posts: 40,951
Kudos: 79,762
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Thanks for the question. I have updated the explanation in the tests and also in the second post of the topic.

SSgmat2024
I think this the explanation isn't clear enough, please elaborate.
User avatar
sssdd1234
Joined: 18 Feb 2023
Last visit: 16 Mar 2025
Posts: 68
Own Kudos:
Given Kudos: 22
Posts: 68
Kudos: 7
Kudos
Add Kudos
Bookmarks
Bookmark this Post
I think this is a high-quality question and I agree with explanation.
User avatar
Aarti0701
Joined: 24 May 2024
Last visit: 18 Dec 2024
Posts: 10
Own Kudos:
Given Kudos: 52
Posts: 10
Kudos: 2
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Even if the 3rd option is right, intelligence can play a role in determining the passing electrician rather than study hours, However option D may be right as they did study extra through different course which other might not have studied. so studying extra hour became the factor
User avatar
bb
User avatar
Founder
Joined: 04 Dec 2002
Last visit: 20 June 2025
Posts: 40,951
Own Kudos:
79,762
 [1]
Given Kudos: 22,664
Location: United States (WA)
GMAT 1: 750 Q49 V42
GPA: 3
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
GMAT 1: 750 Q49 V42
Posts: 40,951
Kudos: 79,762
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Aarti0701
Even if the 3rd option is right, intelligence can play a role in determining the passing electrician rather than study hours, However option D may be right as they did study extra through different course which other might not have studied. so studying extra hour became the factor

This is not a question about what is right but what strengthens the conclusion.

Option D, while could be a real situation, actually weakens the conclusion and is therefore the incorrect answer choice.
Option E, similarly weakens the conclusion.
User avatar
APram
Joined: 23 Jun 2024
Last visit: 20 Jun 2025
Posts: 79
Own Kudos:
45
 [1]
Given Kudos: 114
Location: India
Schools: ISB '26
GMAT Focus 1: 585 Q78 V81 DI81
GPA: 3.608
Products:
Schools: ISB '26
GMAT Focus 1: 585 Q78 V81 DI81
Posts: 79
Kudos: 45
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
I like the solution - it’s helpful.
User avatar
Abhishek_Relan
Joined: 30 Nov 2023
Last visit: 20 Jun 2025
Posts: 5
Given Kudos: 57
Posts: 5
Kudos: 0
Kudos
Add Kudos
Bookmarks
Bookmark this Post
I like the solution - it’s helpful.
User avatar
Sushi_545
Joined: 25 Jan 2024
Last visit: 20 Jun 2025
Posts: 11
Own Kudos:
Given Kudos: 10
Products:
Posts: 11
Kudos: 2
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
Electrician Magazine surveyed 1,000 electricians who took an advanced certification exam. Of these 1,000 candidates 500 passed the exam and 500 failed. The magazine asked the electricians how many hours they had studied for the exam. It was found that those who passed had studied on average 50 hours, and those who failed had studied on average 20 hours. The magazine concluded that the more hours one studies, the more likely they are to pass.

Which of the following, if true, would most strengthen the conclusion of the magazine?


A. Some of the electricians in the survey actually studied more than 100 hours.
B. Many of those surveyed thought the exam was unnecessary and did not reflect on their ability as electricians.
C. The electricians in the survey all took the exam shortly after reaching five years of experience as an electrician.
D. Many of the electricians who passed had completed a course in electronics covering some of the topics also included in the syllabus of the certification exam.
E. Majority of the electricians who failed had college degrees in a variety of fields not related to electrical subjects.

Hi Bunuel, bb, @KarishmaB, @gmatophobia ,@sayantanc2k
C
an anyone help here

If we assume Candidate who have 5 year work exp passed the exam and with 3 year work ex have not. Then isnt this example going against like having more work ex they are studying more hours?

A-> 5hrs -> work ex->5yrs

B-> 3 hrs -> work ex-> 2yr

thats why i have choosen D

here work ex is actually making the person to study longer. how would you justify this?
Moderators:
Math Expert
102214 posts
Founder
40950 posts