Enforcement of local speed limits through police monitoring has proven

You've really answered your own question here. The question stem asks specifically for "a potentially serious drawback to the plan," so that's exactly what you're looking for. If the question is phrased differently, then you'll likely be looking for something different. For example, if the question asked, "Which of the following, if true, shows that the plan is unlikely to accomplish the stated goal?" then you should look for something that... shows that the plan is unlikely to accomplish the stated goal!

There really aren't any effective "rules" to memorize about when to think about the plan vs. the plan's goal. Instead, just answer each question as written. There's no way around reading the exact language and answering that exact question.

For this question, let's say that these speed humps were proposed for your town. If someone stood up in the town meeting and said, "Wait a minute, emergency vehicles such as fire trucks and ambulances will have to slow almost to a stop at speed humps!" then you'd agree that this person has brought up a potentially serious drawback to installing the humps. After all, if your house was on fire, you wouldn't want emergency vehicles to slow down so much as they came to your rescue.

And unfortunately, it's also a waste of time to come up with your own answer choices. Instead, it's much more important to acknowledge that you misread/misinterpreted the question, and that's what caused you to eliminate the correct option. Next time, just slow down a bit on the exact language of the question and answer it as written, instead of trying to match it to other questions that you've seen.

I hope that helps a bit!

Hi avigutman – I am afraid I don’t.

Remember Interpretation of words in English is about the surrounding context

When you read the phrase in green - screenshot below - “Thereby enhance safety in residential neighborhoods” :

What does safety in residential neighborhoods cover ?

From the surrounding context in yellow – the green is referring to safety in the residential neighborhoods BECAUSE OF VEHICLES SPECIFICALLY

So, safety issues such as
- Vehicles crashing into other cars (in neighborhoods)
- Vehicles crashing into pedestrians
- Vehicles crashing into homes / crashing into mailboxes
- Vehicles speeding next to kids' schoolbuses

I didn’t interpret the green as referring to OTHER saftely issues like : burning houses / robbery / theft / mail fraud

The context in the yellow, doesnt imply the green be referring to burning houses / robbery / theft / crime / mail fraud

Hence I personally don’t think option (b) has anything to do with green phrase as the context from the sorrounding yellow , green is referring to vehicular safety specifically.

You’re saying that this quote limits the scope of ‘safety’ to ‘vehicular safety’:You are correct, jabhatta2. The point of the plan is to enhance ‘vehicular safety’ in residential neighborhoods.
My claim is that a GMAT ‘drawback to the plan’ is likely to affect neighborhood safety OTHER than vehicular safety.

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My question is, in option B, isn't this issue of emergency vehicles being stopped is an issue for neighbourhoods as well. And the question specifies about why this would be drawback for the the town Ardane. I thought that it is something specific to Ardane that does not allow this idea to be passed.

Thanks.

Are you thinking that "the neighbourhoods" are somehow different, or separate, from the town of Ardane, VECHAMSRIRAM?

Sorry for the confusion,

I meant the nearby towns of Ardane, my argument here is if the speedbumps were installed in nearby towns, the issue of emergency vehicles would be there in the nearby towns as well. And I understood the question, that what problems will Ardane town face specifically, that is, is there something unique to Ardane that will lead this speed bump plan to be failure.

After which I thought since the speed limit of Ardane is higher when compared to Nearby towns, there could be some issues, and hence I chose option C.

This was your mistake VECHAMSRIRAM
The question didn’t specify that the drawback must be unique. For all we know, the same drawback applies to those neighbouring towns. It’s irrelevant.

Posted from my mobile device

Posted from my mobile device

Conclusion "In order to reduce traffic speed and thereby enhance safety in residential neighborhoods, Ardane's transportation commission plans to install multiple speed humps in those neighborhoods"

The goal here is "reduce traffic speed and enhance safety". So our prediction is that there has to be something that will prevent the plan from achieving its goal, anything that call to question the efficiency of the plan.

A. On residential streets without speed humps, many vehicles travel at speeds more than 25 percent above the posted speed limit. "Not important to our prediction

B. Because of their high weight, emergency vehicles such as fire trucks and ambulances must slow almost to a stop at speed humps.
" Now this fit our prediction. If emergency vehicle have to slow down from a high speed upon approaching a bump. It call to question the goal of enhancing safety.

C. The residential speed limit in Ardane is higher than that of the nearby towns where speed humps were installed. "We are not comparing speed limit but looking for what can prevent of achievement of our goal"

D. Motorists who are not familiar with the streets in Ardane's residential districts would be likely to encounter the speed humps unawares unless warned by signs and painted indicators. "This is a simple problem that has a solution which was mentioned included in the answer choice"

E. Bicyclists generally prefer that speed humps be constructed so as to leave a space on the side of the road where bicycles can travel without going over the humps. "The same as option D"

Imo option B is a setback for the plan

Why is A incorrect?

The question talks about enforecement of speed limits. The question stem tells us that speed bumps help in reducings speed but the magnitude of the benefit is less than 25%. If in this town, people speed by more than 25%, speed bumps probably won't help slow down cars enough for the speed limit to be met.

Answer Choice B is apparently correct but why is it necessary that ambulances slowing for speed bumps is a bad thing? Speeding through lanes is a continous source of danger and I'd give that preference over the occasional ambulance that is slowed down?

As you say, answer choice (A) suggests that the speed humps may not be sufficient to slow down cars enough to meet the speed limit. So what's wrong with answer choice (A)?

First, notice that the town's explicit goal is to "reduce traffic speed and thereby enhance safety in residential neighborhoods." Answer choice (A) doesn't cast any doubt on the likelihood that speed humps would slow down traffic. Even if many drivers don't slow down enough to hit the speed limit, a 20-25% fall in traffic speed would count as a reduction.

Also, notice that the question is specifically asking for a "potentially serious drawback to the plan." That is, it's not asking for a flaw in the reasoning, but rather a "potential drawback" (i.e. a potentially damaging consequence) of the speed humps. So does slowing down emergency vehicles count as a potentially serious consequence of the plan?

Well, as you say, maybe slowing down emergency vehicles would be worth it? But the question doesn't ask us to make that kind of complicated judgment. Maybe the speed humps will prevent more damage than they cause? Maybe they won't? But either way, it's fair to say that slowing down emergency vehicles is a "potentially serious drawback."

So for (B) to be correct, we don't need to conclude that speed humps are ultimately a bad idea. We just need to conclude that slowing down ambulances and firetrucks is a "potentially serious drawback." Since that's a reasonable idea, (B) is correct.

I hope that helps!

I did not give enough attention to the "drawback" element in the question. Thank you! Your explanations across the forum are brilliant.

Your explanatio

Hi skywalker, even though A says that most cars travels at >25% of speed limit, but still there will be some cars which travels between 0-25% excess of speed limit. And speed breakers will be helpful in such cases. Thus overall no. of speeding cars will decrease albeit be a small number, consequently increasing the safety.
Therefore A is not a serious drawback of plan, but a light strengthener.

Why is D incorrect GMATNinja, @Empowergmat. It seems that option states a drawback that motorists can encounter speed humps unaware unless signs are given. Doesnt this pose a serious safety issue?

but if B is the answer, how can the humps worked in the near cities?

Remember what the question is asking specifically: which of the following, if true, identifies a potentially serious drawback to the plan for installing speed humps in Ardane?

A plan can still work even though it has a drawback. You might decide, for example, to start riding your bike to work to save on gas money, but a drawback to that plan is that you'll be exposed to the elements whenever the weather is bad. Your plan works (you'll still get to work and save on gas money), but it has a drawback.

Similarly, the speed humps can work (that is, successfully reduce traffic speeds) even though they have a drawback (the humps slow down emergency vehicles).

Choice (B) tells us a drawback, but having that drawback doesn't mean that the humps won't work.

I hope that helps!

Check out its detailed video solution here: https://youtu.be/PXjBs1FOhzo?feature=shared

Here is a video solution to this problem: https://youtu.be/PXjBs1FOhzo