Critical reasoning OG 13

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Critical reasoning OG 13

by anksm22 » Wed Jul 16, 2014 8:36 am

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In the past, most children who went sledding in the winter snow in Verland used wooden sleds with
runners and steering bars. Ten years ago, smooth plastic sleds became popular; they go faster than
wooden sleds but are harder to steer and slow. The concern that plastic sleds are more dangerous is
clearly borne out by the fact that the number of children injured while sledding was much higher last
winter than it was 10 years ago.

Which of the following, if true in Verland, most
seriously undermines the force of the evidence cited?


(A) A few children still use traditional wooden sleds.
(B) Very few children wear any kind of protective gear, such as helmets, while sledding.
(C) Plastic sleds can be used in a much wider variety of snow conditions than wooden sleds can.
(D) Most sledding injuries occur when a sled collides with a tree, a rock, or another sled.
(E) Because the traditional wooden sleds can carry more than one rider, an accident involving a wooden sled can result in several children being injured.



Please explain this

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by VivianKerr » Wed Jul 16, 2014 11:26 pm

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This is a Weaken question. Before you can read the answer choices, write down your own pre-phrased answer. Since the argument is flawed, you might be able to think of 2-3 ways it can be weakened. Try to hone in on the BIGGEST flaw you can spot. What doesn't make logical sense?

Our notes:

-Wooden in past
-New Plastic sleds faster
-Wooden easier to steer/slow
-Sled injuries HIGHER last winter

Conclusion: Plastic sleds more dangerous

Assumption: More injuries DUE to the switch from wood to plastic

Since this is a cause/effect claim, the easiest way to undermine this would be to show that the rise in child injuries last year is NOT due to steering/slowing. Is there another cause?

(C) provides us with the cause. The plastic sleds themselves aren't to blame. They are being used in MORE conditions, so if there's more sledding then there's likely more accidents. So it's indirect.
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by anksm22 » Sat Jul 19, 2014 7:34 am

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Thanks for the reply.

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by VivianKerr » Mon Jul 21, 2014 11:59 pm

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You're welcome! Notice the key to this Weaken question is the key to MOST GMAT CR: identify the question stem and the expectations that go along with it, take notes on your yellow scratch pad, then make a Prediction for what you think the correct answer should be!

Most people miss CR when they cut corners on strategy. :-) I know I do!
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by ceilidh.erickson » Sun Jul 27, 2014 8:52 am

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You should always question an argument that turns a quantitative metric such as "greater number of injuries" into a qualitative metric such as "less safe."

We're given that a greater NUMBER of children have been injured while sledding than were 10 years ago. Does that have to mean that their sleds are less safe? We should ask:
- Are there more children sledding now than there were 10 years ago?
- Are children sledding more often?
- Is the severity of accidents the same? Safety isn't just defined by number of accidents, but how severe they are.
- Is the difference in sleds the cause of the change, or is there some other behavioral difference in children over 10 years?

If we want to WEAKEN the argument, we need a reason to suggest that number of accidents does not correlate to safety.

(A) A few children still use traditional wooden sleds.
This would strengthen the argument - it's more likely that the injuries were due to the plastic sleds.

(B) Very few children wear any kind of protective gear, such as helmets, while sledding.
Again, this would strengthen - differences in injuries is more likely to be due to the sleds, not protective gear.

(C) Plastic sleds can be used in a much wider variety of snow conditions than wooden sleds can.
Correct! This indicates that children are likely to sled more often. More sledding = more time spent / opportunity for injuries, without implying that the sled is to blame.

(D) Most sledding injuries occur when a sled collides with a tree, a rock, or another sled.
This would be true of wooden and plastic sleds, so it wouldn't help us compare.

(E) Because the traditional wooden sleds can carry more than one rider, an accident involving a wooden sled can result in several children being injured.
Since the metric we're given is "number of children injured," this wouldn't make a difference. If the sled injures one person or multiple people at a time, it could still be judged unsafe.

The answer is C.
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