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Difficulty:
45%
(medium)
Question Stats:
68% (01:52) correct
32%
(02:03)
wrong
based on 1273
sessions
History
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Researchers recently discovered an unusually high concentration of harmful metals in the water supply of Dunbarton county. They further found that, with a costly new water filter system installed in their homes, residents were able to filter out almost all of the harmful metals in the water supply. For this reason, all the residents of Dunbarton county should have the filter system installed in their homes, regardless of expense.
If true, which of the following would most weaken the above conclusion?
A. Researchers could not discover how the harmful metals were entering the water supply.
B. The increased levels of harmful metals were insufficient to result in significant health effects.
C. The researchers failed to investigate the possibility of harmful microorganisms and other contamination in the county's water supply.
D. The researchers found that people who tried to purify their water by boiling it were just as likely to ingest increased levels of harmful metals as people who drank straight from the tap.
E. Researchers found that, over time, the levels of harmful metals in the water supply did not vary significantly and remained consistently high.
If true, which of the following would most weaken the above conclusion?
A. Researchers could not discover how the harmful metals were entering the water supply.
B. The increased levels of harmful metals were insufficient to result in significant health effects.
C. The researchers failed to investigate the possibility of harmful microorganisms and other contamination in the county's water supply.
D. The researchers found that people who tried to purify their water by boiling it were just as likely to ingest increased levels of harmful metals as people who drank straight from the tap.
E. Researchers found that, over time, the levels of harmful metals in the water supply did not vary significantly and remained consistently high.
mrinal0308
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WE:Information Technology (Computer Software)
GMAT 1: 680 Q50 V31
Posts: 93
Ans : B
Because if there are no significant health hazards happening due to intake of this water, there is no necessity of installing the expensive equipment to filter water at home. Hence the argument is weakened.
Because if there are no significant health hazards happening due to intake of this water, there is no necessity of installing the expensive equipment to filter water at home. Hence the argument is weakened.
chesstitans
Joined: 12 Dec 2016
Last visit: 20 Nov 2019
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Schools: Stanford '19 Carroll '19 LBS '19
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"For this reason" indicates that there is only one main premise.
There are 2 or 3 patterns in option choices.
There are 2 or 3 patterns in option choices.
Can you explain why C is not the correct choice ..
I was stuck between b and c
I was stuck between b and c
lybeaver
Joined: 04 Jun 2018
Last visit: 03 Nov 2021
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Location: Viet Nam
Concentration: Strategy, Operations
Schools: Rotman '22 (A$)
GMAT 1: 610 Q47 V27
GMAT 2: 620 Q46 V29
GMAT 3: 680 Q47 V36
Well, I put B in the contender, but then I rejected B because of the word "significant health effects", the increased levels of harmful metals were insufficent to result in significant health effects, but it actually can result in unsignificant health effects or health effects in general, therefore, the residents should have the filter system installed in their homes. Then this choice should strengthen the plan
Please correct my reasoning above. Thanks!
Please correct my reasoning above. Thanks!
XyLan
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lybeaver
lybeaver, It's good to be watchful!
However, Let's Deep-dive!
Conclusion:
- New WaterFlterSystem filters almost all ---------> All the residents SHOULD have the WaterFlterSystem installed in their homes, regardless of expense.
Pre-Think:
- Assumption: The increased levels of harmful metals are harmful ENOUGH to cause adverse effects on health.
B. The increased levels of harmful metals were insufficient to result in significant health effects.
- If the increased levels of harmful metals were INSUFFICIENT to result in significant health effects, then WHY should the residents NEED to install it.
- That too, at whatever expense.
To answer your query:
Quote:
- Notice the passage states that the increased levels are INSUFFICIENT to result in significant health effects.
Implying, - it actually CAN result in insignificant health effects or health effects in general., is an inference mistake of the answer choice.
- Did OptionB states that the increased levels of harmful metals were sufficient ENOUGH to affect in health effects OR health effects in general? NO.
- If one does NOT study diligently and work hard --------> One would fail.
- Does it imply?
- NO. It's NOT necessarily conclusive. There might be other factors such as test-taking ability, test-surroundings, mindset, mental condition, etc.
You did an error of mistaken-negation of a conditional statement.
- If X ------> Y
- ----- does NOT imply ----->
- If NOT X ------> NOT Y
- Something CAN does NOT necessarily mean it ACTUALLY does, unless backed by the coherent answer choice. - Capacity vs Certainty
Even if increased levels CAN result in insignificant health effects, the effects are STILL insignificant. - Unlikely to cause adverse health hazard/issue.
TakeAway:
- You lose this Q not because you did not know how a weakener works (Infact, I believe you very well do!) , but because you did an inference mistake from a right-answer choice. - An unintended yet, costly mistake in GMAT.
Always ASPIRE to find 4 incorrect answer choices.
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lybeaver
Joined: 04 Jun 2018
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Xylan: Thanks so much! Your explanation is an eye opener!
IMO B
Conclusion : residents should install filters due to increased metals .
If the increased metals have no negative health impact , then why we should filter them .
We do not need filter at all.
So B is correct answer .
Posted from my mobile device
Conclusion : residents should install filters due to increased metals .
If the increased metals have no negative health impact , then why we should filter them .
We do not need filter at all.
So B is correct answer .
Posted from my mobile device
mokiburnsred
Joined: 20 Sep 2018
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Schools: EDHEC MiM "22 (II)
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I was down to B and E and chose E in the end. Could someone please tell me why E was eliminated?
VirFortis
Joined: 08 Mar 2021
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What is the source of this question?
There is no mention of the information - that the level of contamination has increased. It just says that high level of contamination is found.
So, option B suggesting the "increased" contamination seems out of context while option C which states that the other contamination can also be part of the water seems like something to weaken the conclusion but again it doesn't talk about the fact if the filter can help with those.
So, the argument of installing the filter based on the fact that almost all harmful contamination is removed by it is shaky at its core.
Posted from my mobile device
There is no mention of the information - that the level of contamination has increased. It just says that high level of contamination is found.
So, option B suggesting the "increased" contamination seems out of context while option C which states that the other contamination can also be part of the water seems like something to weaken the conclusion but again it doesn't talk about the fact if the filter can help with those.
So, the argument of installing the filter based on the fact that almost all harmful contamination is removed by it is shaky at its core.
Posted from my mobile device
VirFortis
Joined: 08 Mar 2021
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XyLan
Sorry, but I am not able yo find - "increased level" - causing harm statement in the passage. Rather it says - High level contamination - > causes harm - > filter helps - > install filter. So we should attack premise - filter helps.
What am I doing wrong here?
Please guide me.
Posted from my mobile device
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