#10 - If a person chooses to walk rather than drive, there

[Jay Donnell]

Hi Jerry!

The error behind C is one that actually shows up a decent amount in incorrect answers, so I want to help clear it up.

The author is arguing that by reducing the amount of vehicles used (replaced by people walking in lieu of driving) would lead to a reduction in the amount of pollution.

C tells us that certain cars pollute more than others (which is reasonable considering SUVs versus hybrids, for example), but knowing that cars are on a scale for pollution does not help us to strengthen the argument that removing the use of cars will help with the reduction of pollution.

Maybe, all the people who decide to ditch their cars and walk to work or social events are the people who owned cars that were relatively good on the pollution scale. This idea could even weaken the argument, as the pollution decrease wouldn't be as great if it was only the Prius users who were giving up the use of their cars.

Without knowing which cars (and where they are on the pollution spectrum) are being skipped in favor of walking, this information becomes fairly irrelevant in helping to argue that in general, less use of cars will lead to less pollution.

In a similar situation, there was a strengthen question years ago that had something to do with a a special diet that allegedly led to making people healthier. Does knowing that some users of the diet had increases in health that were significantly different than others help to argue that the diet was actually causing increased health? It doesn't, much in the same way as answer choice C in this question.

Hope that helps!

[Jerrymakehabit]

Hi Jerry!

The error behind C is one that actually shows up a decent amount in incorrect answers, so I want to help clear it up.

The author is arguing that by reducing the amount of vehicles used (replaced by people walking in lieu of driving) would lead t a reduction in the amount of pollution.

C tells us that certain cars pollute more than others (which is reasonable considering SUVs versus hybrids, for example), but knowing that cars are on a scale for pollution does not help us to strengthen the argument that removing the use of cars will help with the reduction of pollution.

Maybe, all the people who decide to ditch their cars and walk to work or social events are the people who owned cars that were relatively good on the pollution scale. This idea could even weaken the argument, as the pollution decrease wouldn't be as great if it was only the Prius users who were giving up the use of their cars.

Without knowing which cars (and where they are on the pollution spectrum) are being skipped in favor of walking, this information becomes fairly irrelevant in helping to argue that in general, less use of cars will lead to less pollution.

In a similar situation, there was a strengthen question years ago that had something to do with a a special diet that allegedly led to making people healthier. Does knowing that some users of the diet had increases in health that were significantly different than others help to argue that the diet was actually causing increased health? It doesn't, much in the same way as answer choice C in this question.

Hope that helps!

Thank you Jay! I like the example you gave below. It could undermine the conclusion that pollution will be greatly reduced.

"Maybe, all the people who decide to ditch their cars and walk to work or social events are the people who owned cars that were relatively good on the pollution scale. This idea could even weaken the argument, as the pollution decrease wouldn't be as great if it was only the Prius users who were giving up the use of their cars."

[Jay Donnell]

You're welcome, Jerry!

Maybe I better walk to my tutoring this week and leave my SUV at home

[Jerrymakehabit]

You're welcome, Jerry!

Maybe I better walk to my tutoring this week and leave my SUV at home

Hey Jay,

I was reviewing the explanations again and have a concern here which would like to be clarified.
Using your example, even though only the Prius users who were giving up the use of their cars would not contribute to the decrease of the pollution as much as the SUV users who were giving up the use of their cars, Prius users still help to reduce in the amount of pollution. So the problem is actually that it does not help with the conclusion "pollution will be greatly reduced". Is my understanding correct?

Thanks
Jerry

[Jay Donnell]

Hi Jerry!

Yes, the big issue is that the answer bringing in the existence of the scale of polluting vehicles doesn't (really at all) help to strengthen the argument. Especially, as you pointed out, the author concluded a rather bold point with claiming that due to this plan, pollution would be "greatly reduced." Similarly, the low language strength of C with its use of "possible" is another detrimental factor in this case.

Thanks to you, I've been using my motorcycle instead of my car to get to my local tutoring students these past few days. Baby steps at least toward curbing pollution... you're welcome, environment!

[Jerrymakehabit]

Hi Jerry!

Yes, the big issue is that the answer bringing in the existence of the scale of polluting vehicles doesn't (really at all) help to strengthen the argument. Especially, as you pointed out, the author concluded a rather bold point with claiming that due to this plan, pollution would be "greatly reduced." Similarly, the low language strength of C with its use of "possible" is another detrimental factor in this case.

Thanks to you, I've been using my motorcycle instead of my car to get to my local tutoring students these past few days. Baby steps at least toward curbing pollution... you're welcome, environment!

Thank you Jay! You are assuming the environment said thank you and your motorcycle is curbing pollution (air and noise )

[treschdawg]

It still doesn't make sense to me how answer B is correct. Here is an example I came up with using the logic in answer B that seems to weaken, not strengthen, the argument in the stimulus:

If there are 20 cars on a congested road, they are polluting at a rate of 0.5 (total pollution = 10)
If 10 of these people are able to walk instead, there are now only 10 cars on the road and there is no congestion, so the 10 cars are polluting at a rate of 1 (total pollution = 10)

Therefore, in this example, the 10 people deciding to walk instead had absolutely ZERO impact on total pollution. This is the opposite outcome of the argument in the stimulus: "if people would walk whenever feasible for them to do so, then pollution will be greatly reduced."

Although none of the answers popped out at me, I settled for answer C because if some cars pollute more than others, this only strengthens the claim that walking will cause pollution to be greatly reduced. If every car were a Prius, the author's argument wouldn't be terribly compelling ("greatly" reduced may be a stretch). But since we know that Hummers pollute more than Priuses, we can infer that people who walk instead of driving their Hummer will in fact reduce pollution relatively more.

Please let me know how where I went wrong with my logic. Thanks.

[Jeremy Press]

Hi tresch,

Francis actually did a really nice job of answering this in the second post in the thread, but the problem with your hypo is that answer choice B shows us there is an extra contribution to pollution from "nonmoving" cars. But since they contribute half as much pollution even when they're not moving, they contribute an additional amount (double that nonmoving level) when they start moving again. And of course they have to move to get to their destinations. So if we remove congestion by having more people walk, there's actually no way for the pollution level to "equal out," given the scenario described by answer choice B. In other words, your scenario goes wrong because it doesn't allow for any extra contribution from the nonmoving cars when they start moving again (as we know they will). Make sense?

As for answer choice C, I don't think I can do better than Jay's explanation above, so take another quick look at that one and see if that clears it up!

Jeremy

[ericj_williams]

If the argument is that one vehicle can greatly reduce the amount of pollution, doesn't C strengthen this?

Isn't C confirming the possibility that one person can in fact greatly reduce pollution?

[Dave Killoran]

If the argument is that one vehicle can greatly reduce the amount of pollution, doesn't C strengthen this?

Isn't C confirming the possibility that one person can in fact greatly reduce pollution?

This has never been my favorite problem but I'd say you're not going to see a better explanation than Jay's at the top of this page. I don't think I can do better, so we'll let that stand here as the explanation.

I'd also refer you to a comment I just made on another of your posts: don't look at why you think these answers are right, try to figure out why LSAC thinks they are wrong