the city of Los Diablos

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the city of Los Diablos

by Mani_mba » Wed Oct 01, 2008 8:52 pm
A question from 1000 CR.

In 1986, the city of Los Diablos had 20 days on which air pollution reached unhealthful amounts and a smog alert was put into effect. In early 1987, new air pollution control measures were enacted, but the city had smog alerts on 31 days that year and on 39 days the following year. In 1989, however, the number of smog alerts in Los Diablos dropped to sixteen. The main air pollutants in Los Diablos are ozone and carbon monoxide, and since 1986 the levels of both have been monitored by gas spectrography.
Which of the following statements, assuming that each is true, would be LEAST helpful in explaining the air pollution levels in Los Diablos between 1986 and 1989?
(A) The 1987 air pollution control measures enacted in Los Diablos were put into effect in November of 1988.
(B) In December of 1988 a new and far more accurate gas spectrometer was invented.
(C) In February of 1989, the Pollution Control Board of Los Diablos revised the scale used to determine the amount of air pollution considered unhealthful.
(D) In 1988 the mayor of Los Diablos was found to have accepted large campaign donations from local industries and to have exempted those same industries from air pollution control measures.
(E) Excess ozone and carbon monoxide require a minimum of two years to break down naturally in the atmosphere above a given area.

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by codesnooker » Thu Oct 02, 2008 9:05 am
IMO B.

B. In December of 1988 a new and far more accurate gas spectrometer was invented.

The above statements state that more accurate gas spectrometer was invented but it never said that this more accurate gas spectrometer is used to check the previous year gas levels or even if used then also didn't mention the degree of flaw in the previous recordings.

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by saurabh_dce08 » Fri Oct 03, 2008 9:37 pm
although the OA is B
But i don't agree with that....

can you pls explain how can option D help explaining the decrease in the
levels of smog in 1989...


Ron or stuart pls help on this one?

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by Bidisha800 » Sat Oct 11, 2008 11:18 pm
Invention of an accurate tool doesn't suggest that the tool was ever used !

A new gas spectrometer or whatever it is was invented that year but was it used to measure the air pollution ? No !
Therefore, how this invention is related to explanation of pollution measurement ?

(B) is correct.

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by rdxb » Sat Oct 11, 2008 11:43 pm
Invention of an accurate tool doesn't suggest that the tool was ever used !

A new gas spectrometer or whatever it is was invented that year but was it used to measure the air pollution ? No !
Therefore, how this invention is related to explanation of pollution measurement ?

(B) is correct.
Although I agree with (B), as the invention doesn't itself prove that the instrument was used, I am not able to understand how (D) HELPS in explaining the levels.

If some small companies were exempt from the control measures, the pollution levels wouldn't decrease, would they?

Let me know if I missed smthing there.

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by Jatinder » Sun Oct 12, 2008 6:14 am
But through that codesnooker's reasoning...what is the problem in E
E, also says that it wll take 2 yesrs to brake down....we don't have any info ...that pollution level will increase if they brake down ?

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by gmat009 » Thu Nov 06, 2008 12:09 pm
Can someone plz. explain why D is better than B.

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by stop@800 » Thu Nov 06, 2008 7:21 pm
My reasoning for invalidating D and E

D
mayor exempted some industries from pollution control measures
had the industries been more polluting the level will certainly decrease

E
it says that level is observed after two years
hence that measures inacted led to decrease in pollution level
so it gives proper reason

Hope thsi helps!!

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by Karen » Fri Nov 07, 2008 6:34 pm
The question isn't primarily why the pollution levels dropped in 1989. It's why pollution levels continued to rise after pollution control laws were enacted. "Between 1986 and 1989" is ambiguous -- it may not even include 1989 itself; it may mean only 1987 and 1988. In any case, the focus is clearly on the paradoxical rise in air pollution in 1987 and 1988, and B does not explain that. Even if the apparent drop in pollution in 1989 was due to better measurements, there's no explanation there of why pollution levels appeared to be rising in the previous two years despite new legislation.

D is not the answer because if the mayor exempted some local industries from the new regulations, that *would* help to explain why pollution levels continued to rise.
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by xyzabc123 » Sat Nov 29, 2008 3:58 pm
Karen is right. (B) only explains the drop but not the increase and that's why it is the right answer.
But (C) does not explain the increase either. It seems to be a good candidate too.
Please, explain.

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by Karen » Sat Nov 29, 2008 6:23 pm
C offers an explanation that's a different way of looking at it -- maybe the pollution levels didn't drop; maybe they just changed the threshold that determines when to call a smog alert. So that could explain the discrepancy too.
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by corleone » Wed Jan 28, 2009 3:01 am
Karen wrote:The question isn't primarily why the pollution levels dropped in 1989. It's why pollution levels continued to rise after pollution control laws were enacted. "Between 1986 and 1989" is ambiguous -- it may not even include 1989 itself; it may mean only 1987 and 1988. In any case, the focus is clearly on the paradoxical rise in air pollution in 1987 and 1988, and B does not explain that. Even if the apparent drop in pollution in 1989 was due to better measurements, there's no explanation there of why pollution levels appeared to be rising in the previous two years despite new legislation.

D is not the answer because if the mayor exempted some local industries from the new regulations, that *would* help to explain why pollution levels continued to rise.
Hey Karen,

Here is my take on the argument. Am another proponent of choice D.

B says that a more accurate instrument was invented in DECEMBER 1988. Assuming that this was used next year (in 1989), the levels of carbon monoxide etc would be more precisely noted. It might be the case that instrument used earlier gave a higher reading and hence the higher number of smog alerts.

D says that in in 1988 the mayor exempt some industries from pollution checks. This action DOES NOT explain any rise in pollution. It also does not explain the reduction of smog alerts. Hence D should be the answer.

I'd love to hear your reasoning on this one.

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A New ENtry

by moneywise » Thu Jan 29, 2009 2:18 am
Hi,
I think B gives an impression of helping identify as to why the levels went down after 1989.But as,others mentioned,it is never mentioned whether the new instrument was ever used.
Hence B should be the correct answer

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by gmatmachoman » Fri Nov 20, 2009 11:55 am
Guy I want to reopen this thread...


I am completely lost here...I could see people proposing B or D..But I couldnt derive any logic here..

Plz help me out with some logical explanations...

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by Testluv » Fri Nov 20, 2009 1:19 pm
gmatmachoman wrote:Guy I want to reopen this thread...


I am completely lost here...I could see people proposing B or D..But I couldnt derive any logic here..

Plz help me out with some logical explanations...
Who cares?!

This is a garbage 1000cr question. You may as well have some random person design a question, and then feel bad because you can't choose between two answers. Practicing on these questions can HURT you more than it can help you.

People think more questions, more practice, better off. But if the kind of questions you are working on are badly designed then a reason for why a right answer is right or why a wrong answer is wrong may not even be applicable on real GMAT questions. You might take away learnings that are bad information on the real test!
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