voodoochild wrote:
question#1 - I have no issues with OA D. I actually chose that while answering this question. However, I am curious about A). Setting aside the main issue about environment and safety, I feel that A) hinges on a minor gap in the argument : Premise talks about "more slowly a car is driven .... " but the conclusion is about "reducing speed limit ". I feel that A) is trying to attack this gap. Essentially, just because the speed limits are reduced, the drivers won't have an incentive to drive slowly. If there are some drivers who don't follow the speed limits, then wouldn't this weaken the connection between driving slowly and speed limits --- drivers don't obey speed limits at all.
Also, I have also read in one of the CR notes floating in the forum that negation of sufficient conditions are generally out of scope.
Honestly, I think at this point, you would be better off on CR, more successful and more efficient, if you purged the words "necessary" and "sufficient" from your mind.
Here the original argument:
Reducing speed limits neither saves lives nor protects the environment. This is because the more slowly a car is driven, the more time it spends on the road spewing exhaust into the air and running the risk of colliding with other vehicles.Clearly, this is a statistical argument --- if most of the cars go slower, you will get these problems. There is no reality, real or imagined, in which every driver on the road drives exactly at the speed limit --- there will always be slower and faster drivers. The effect of setting a certain speed limit, or reducing the speed limit, is to move where the central hump of the bell curve of speeds falls. The fact that some drivers speed is in no way a "hole" in this argument.
The question asks:
The argument’s reasoning is flawed because the argumentWe need a weakener, something that will undermine the evidence or assumption. Well, if a few select drivers are drive much faster than the speed limit, they place other slower drivers at risk --- the most dangerous condition is not uniform high speed, but larger differentials in speed. That actually strengthens the argument.
I guess the really big question is --- if you know what the right answer is, and have no problem with it, why are you dissecting wrong answers like this? Yes, it's important to understand why wrong answers are wrong, but it's not at all clear to me whether the level of attention you give to incorrect answer has not crossed the threshold of diminishing returns and whether it's now counterproductive in terms of efficiency.
voodoochild wrote:
question #2 -
to give an example :
Baseball players, who wear white shirt, always score a home run in their league matches.
Hence, Baseball players who wear white shirt help in winning the game.
OK, here I think there are some grammar points you don't understand, and they are befuddling the argument. Where you put the commas has big logical consequences. See these two posts:
https://magoosh.com/gmat/2012/that-vs-which-on-the-gmat/https://magoosh.com/gmat/2012/gmat-gramm ... modifiers/Also, the words you use to describe baseball are not idiomatically correct --- players don't "score" home runs, but rather "hit" home runs; and the contests are called "games", never "matches". The entire sentence is, in the context of baseball, completely unrealistic, so I will change it a bit.
Consider these two sentences:
a)
Baseball players, who make a great deal of money, seem not to work very hard. b)
Baseball players who make a great deal of money seem not to work very hard. Do you understand the logical difference in those two sentences? They say
very different things.
The first is a comment about
all baseball players, and attribute two things to all of them -- making a great deal of money and not working very hard.
The second is isolates a particular group of players, only those who make a great deal of money, and makes a comment specific to them.
Your first sentence was, "Baseball players, who wear white shirt, always score a home run in their league matches." That sentence implies, among other things, that all baseball players wear white shirts and that all baseball players are part of this discussion. Then, you ask about ."Baseball players who don't wear white shirt...." --- that would be an impossibility, given your first statement.
Whether you set off a modifying clause by commas from the rest of the sentence has huge logical implications for the meaning of the sentence.
Does that make sense?
Mike
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Mike McGarry
Magoosh Test PrepEducation is not the filling of a pail, but the lighting of a fire. — William Butler Yeats (1865 – 1939)