OG DIAG 32

This topic has expert replies
Master | Next Rank: 500 Posts
Posts: 273
Joined: Thu Sep 08, 2011 6:50 am
Thanked: 5 times
Followed by:3 members

OG DIAG 32

by fangtray » Sat Mar 31, 2012 4:29 pm
For years the beautiful Renaissance buildings in Palitito have been damaged by exhaust from the many tour buses that come to the city. There has been little parking space, so most buses have idled at the curb during each stop on their tour, and idling produces as much exhaust as driving. The city has now provided parking that accommodates a third of the tour buses, so damage to Palitito's buildings from the buses' exhaust will diminish significantly.

Which of the following, if true, most strongly supports the argument?

a. The exhaust from Palitito's few automobiles is not a significant threat to Palitito's buildings/
b. Palitoto's Renaissance bildings are not threatened by pollution other than engine exhaust.
c. Tour buses typically spend less than one-quarter of the time they are in Palitito transporting passengers from one site to another.
d. More tourists come to Palitito by tour bus than by any other means of transportation.
e. Some of the tour buses that are unable to find parking drive around Palitot while their passengers are visiting a site.

In this problem, exhaust from tour bus idling (x) causes damage of buildings (y).
Conclusion: damage to buildings will diminish significantly.

a. this answer elminates an alternate possible cause for Y suggesting that other than tour buses, the buildings are not harmed by other few automobiles. SO it strengthens the argument/conclusion.

b. this answer also eliminates another possible cause for Y. So strengthens. Consider this: If it were a weaken quesiton, and statement B said the opposite: "Palitito's Renaissance buildings ARE threated by pollution other than engine exhaust". This statement would weaken the argument that damage from Palitito's buildings will be reduced significantly, because it gives info that perhaps Z (other pollution) causes Y (damage to buildings) instead of X causes Y scenario in the stimulus.

C. correct answer. The OG justifies this by saying that the buses are idle most of the time, exactly 3/4s of the time, as opposed to just a short amount of time. But the stimulus states SPECIFICALLY that the buildings are damaged from tour buses's exhaust while they are idle at the tour. This could by idling from 1% or 100%, it doesn't state in the stimulus that tour buses only harm the buildings if they are there for a large percentage of time. Even if they are only idle for 1% of the time, they could harm the building, and the new parking spaces could be reducing idle time, thus reducing damage to Palitito's buildings. Why does it have to be 75% of the time?


PLEASE HELP!!
Source: — Critical Reasoning |

User avatar
GMAT Instructor
Posts: 1248
Joined: Thu Mar 29, 2012 2:57 pm
Location: Everywhere
Thanked: 503 times
Followed by:192 members
GMAT Score:780

by Bill@VeritasPrep » Sat Mar 31, 2012 4:35 pm
The conclusion is that building damage caused by buses will decrease.

A--We don't care about automobiles since we're looking solely at damage caused by buses.
B--Again, exhaust sources that aren't buses are irrelevant
C--The amount of time spent idling in front of buildings is relevant. If buses spend 1% of their time idling in front of buildings, then allowing 1/3 of buses to park will reduce the time spent to 2/3%. Not a very big decrease, really. If buses spend 75% of their time idling, then allowing 1/3 of them to park will reduce the time spent to 50%. That's a pretty large change.
Join Veritas Prep's 2010 Instructor of the Year, Matt Douglas for GMATT Mondays

Visit the Veritas Prep Blog

Try the FREE Veritas Prep Practice Test

Master | Next Rank: 500 Posts
Posts: 273
Joined: Thu Sep 08, 2011 6:50 am
Thanked: 5 times
Followed by:3 members

by fangtray » Sat Mar 31, 2012 5:11 pm
Bill@VeritasPrep wrote:The conclusion is that building damage caused by buses will decrease.

A--We don't care about automobiles since we're looking solely at damage caused by buses.
B--Again, exhaust sources that aren't buses are irrelevant
C--The amount of time spent idling in front of buildings is relevant. If buses spend 1% of their time idling in front of buildings, then allowing 1/3 of buses to park will reduce the time spent to 2/3%. Not a very big decrease, really. If buses spend 75% of their time idling, then allowing 1/3 of them to park will reduce the time spent to 50%. That's a pretty large change.
but in A and B, aren't you eliminating other outside factors, which is one of the main ways to strengthen a cause and effect relationship?

User avatar
GMAT Instructor
Posts: 1248
Joined: Thu Mar 29, 2012 2:57 pm
Location: Everywhere
Thanked: 503 times
Followed by:192 members
GMAT Score:780

by Bill@VeritasPrep » Sat Mar 31, 2012 5:14 pm
If the conclusion were simply that damage to the buildings will decrease, then yes, those could be potential answers. However, the exact wording is that "damage to Palitito's buildings from the buses' exhaust will diminish significantly." This means that we're only concerned with the buses.
Join Veritas Prep's 2010 Instructor of the Year, Matt Douglas for GMATT Mondays

Visit the Veritas Prep Blog

Try the FREE Veritas Prep Practice Test

Master | Next Rank: 500 Posts
Posts: 273
Joined: Thu Sep 08, 2011 6:50 am
Thanked: 5 times
Followed by:3 members

by fangtray » Sat Mar 31, 2012 5:22 pm
Bill@VeritasPrep wrote:If the conclusion were simply that damage to the buildings will decrease, then yes, those could be potential answers. However, the exact wording is that "damage to Palitito's buildings from the buses' exhaust will diminish significantly." This means that we're only concerned with the buses.
AHHH... I think i know what you mean...we just want to support that parking will decrease damage..

and A and B do not work, because we are concerned with ONLY decrease, not the elimination of damage. Am I correct? Because if the conclusion stated that damage was completely eliminated, then A and B would definitely strengthen the argument right?

User avatar
GMAT Instructor
Posts: 1248
Joined: Thu Mar 29, 2012 2:57 pm
Location: Everywhere
Thanked: 503 times
Followed by:192 members
GMAT Score:780

by Bill@VeritasPrep » Sat Mar 31, 2012 5:32 pm
Exactly! The stimulus isn't arguing that the building damage is going away entirely (there are many unaddressed factors, such as Godzilla attacks!), just that the contribution from bus exhaust will decrease.
Join Veritas Prep's 2010 Instructor of the Year, Matt Douglas for GMATT Mondays

Visit the Veritas Prep Blog

Try the FREE Veritas Prep Practice Test