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LSAT Explanations › Preptest 143 › Logical Reasoning › Question 21

LSAT 143 | Section 1 | Logical Reasoning: Q21

LSAT Preptest 143 explanations

LR Question 21 Explanation

QUESTION TEXT: A new device uses the global positioning system to…

QUESTION TYPE: Paradox

CONCLUSION: Ranchers will probably buy the device.

REASONING: The device makes noises in cows’ ears when they leave pasture, causing them to turn around. Buying the devices for an entire herd would be much more expensive than using fencing.

ANALYSIS: The device offers the same benefits as fences, but it costs more to outfit the entire herd. So there are only three reasons that ranchers would buy devices at current prices:

  • Ranchers don’t mind paying more for no benefit.
  • Ranchers are idiots.
  • The entire cow herd doesn’t have to be outfitted with the devices.

The first two are not very good explanations. The third one I prephrased. How do you prephrase answers? Put yourself in the shoes of the ranchers. Assume you’re not an idiot. What might make you buy the device, even though outfitting your entire herd would be too expensive?

___________

  1. This is irrelevant. The device makers are saying that ranchers will buy now, at current prices.
  2. CORRECT. If this is true, then ranchers wouldn’t have to outfit their entire herd with the devices. They could just outfit a few cattle leaders with the devices.
    So devices could be cheaper than fences.
  3. This is good. If this weren’t true, the argument would be weaker. But this doesn’t strengthen the argument. We have no evidence that fences are a major cause of stress, so this doesn’t show that devices have an advantage.
  4. Like C, this doesn’t offer an advantage for the devices. It merely places them on the same playing field as fences.
  5. This is a bit of a trick answer. The stimulus says that outfitting an entire herd is too expensive. “The cost of outfitting an entire herd” would include any bulk discounts. Just like “the cost of buying ten subway passes” includes any discount you’d get for buying 10 or more passes.
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More Resources for Paradox Questions

  • Intro Course lesson: This intro course lesson covers Paradox questions.
  • Mastery Seminar lesson: This LR Mastery seminar lesson covers paradox questions.
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Comments

  1. Daniel says Member

    July 24, 2020 at 2:16 pm

    The question text says that “outfitting ALL of the cattle…” so why is B correct?

    Reply
    • Rosalie (LSATHacks) says Tutor

      September 1, 2020 at 3:57 pm

      The text saying “outfitting all of the cattle is far more expensive” removes it as an option since it’s more expensive than fences. However, the stimulus doesn’t talk about the cost of outfitting not all of the cows. If even outfitting all but one of the cows with the device is effective and is cheaper than fences, then it becomes a viable solution. B says that cows like to follow certain members in the pack. Thus, if you put the devices on those certain members, the device will make noise and steer those leader cows back to the home range. And the rest of the cows will follow.

      Reply
  2. Jane says

    September 4, 2017 at 3:32 am

    I debated between B and E. I was conflicted because in picking answer choice B, I’d be assuming that the cost of a few GPS devices would be less than that of a fence when there’s no indication of that–we’re only given information about the expense of outfitting the WHOLE herd. I wasn’t super satisfied with E, because I also figured I couldn’t assume whether or not the current price included the significant discount or out, but because I ruled out answer choice B, I went with E. When is it safe to make assumptions on the LSAT?

    Reply
    • Lucas (LSAT Hacks) says Tutor

      September 4, 2017 at 10:35 am

      Good question. It’s important to remember that sometimes the right answer on strengthen questions isn’t something that will certainly strengthen the reasoning in the stimulus (this is also a principle we can apply elsewhere on the LSAT by the way). Often, the correct answer will just provide a potential means of strengthening the reasoning and that means will be the best of the five choices and/or will rely on the least outside assumptions and/or the answer choice will expect us to make a common sense assumption in order to use it to strengthen the reasoning.

      For example, in this case, we can use common sense to say that if we only need to outfit a few cows with the devices, then there’s a good chance that the devices will cost less than fencing an entire farm, or perhaps will be much more convenient than construction. (E), on the other hand, is incorrect because the stimulus clearly says that outfitting the entire herd (i.e. buying in bulk) will cost far more than fencing. We can use common sense to say that that price must already include the discount — why would the stimulus say it costs more if a discount is available?

      Reply
  3. Max says Member

    August 26, 2017 at 12:47 pm

    I came up with a different pre-phrase that the writers didn’t go with, which is “The money saved by not losing any more cows using the GPS system vs normal fences far outstrips the cost of outfitting all the cows with the GPS”

    Reply
    • Lucas (LSAT Hacks) says Tutor

      August 30, 2017 at 3:08 pm

      You were definitely right to come up with a potential explanation for why the ranchers would purchase the devices over the fencing despite the cost. Occasionally, prephrases don’t match the correct answer choice, that’s why it’s important to stay flexible with your expectations as to what the correct answer choice will be. That being said, coming up with prephrases for as many questions as you can (sometimes you won’t be able to prephrase) is always a great practice — it ensures that you breakdown and analyze the argument in the stimulus, and try to spot gaps in the reasoning.

      Reply
  4. Brian says

    December 2, 2015 at 12:08 am

    Thanks for the awesome website!

    When are you releasing PT 76?? Hopefully before this Saturday’s exam :)

    The conclusion makes a prediction about why the ranchers will purchase the device as it CURRENT price. E discusses a situation where a farmer has so many cow’s that he or she would get a discount if the device was purchased in bulk. But if they are purchasing at a discounted rate, it still doesn’t explain why a rancher would purchase the device at its “current price.” Thus E is wrong.

    Reply
    • Graeme Blake says Founder

      February 19, 2016 at 3:32 am

      No, that’s not right. For example, the current price of a subway ticket in my city is 3.25. But it’s also 25 for 10. “Current price” can include the possibility of a discount.

      76 is out now. Took longer than usual due to some technical stuff.

      Reply

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