Reading comp PrepTest 129 · Section 4 · Question 21

Passage

Questions 20-27  .        Fractal geometry is a mathematical theory devoted  . to the study of complex shapes called fractals. Remaining source text redacted.
Passage walkthrough
Passage Summary

Topic: Science


Paragraph 1

  • Paragraph note
    • Fractals explained (self-similar — each part looks like the whole) and Koch curve example ( _^_, each segment also looks like _^_ )
  • Views, minor Meta-Structures, and the author's attitude
    • Definition of "self-similarity": A shape where each little part looks like the whole shape (second sentence)
    • Example of an important fractal that exhibits self-similarity, according to the author:
      • The Koch curve, which is a straight line with a bump in the middle, but each smaller line has bump, repeated ad infinitum (third through last sentence)
    • Author's attitude: "significant" (third sentence); "provides some insight" (third sentence)

Paragraph 2

  • Paragraph note
    • Use of computers in fractal geometry (not limited by what can be drawn/displayed, so can create more complex fractals)
  • Views, minor Meta-Structures, and the author's attitude
    • Author's view:
      • Computers illustrate why many people are interested in fractals, given that programming simple steps can create very complex patterns (last sentence)
    • Comparison, according to the author:
      • Creating an image of the Koch curve without a computer will be limited by how small we can draw or display each line segment; however, using computers to make Koch curves doesn't have such a limit (third and fourth sentences)
    • Author's attitude: "dramatically illustrates a major attraction" (last sentence); "simple processes" (last sentence); "incredibly complex patterns" (last sentence)

Paragraph 3

  • Paragraph note
    • Debate over usefulness between enthusiasts (a new form of math that can describe complex natural forms) and skeptics (hasn't yet created theorems/proofs)
  • Views, minor Meta-Structures, and the author's attitude
    • Public's view:
      • Captivated by complex images (first sentence)
    • Fractal enthusiasts' view:
      • Fraticals represent a new mathematical system that can describe natural/mathematical forms (first and second sentences)
    • Comparisons, according to the fractal enthusiasts:
      • Fractal geometry will become as important as calculus (second sentence)
      • Fractal will allow mathematicians to describe the shape of a cloud as easily as architects can describe a house with traditional geometry (second sentence)
    • Fractal skeptics' view:
      • Fractal enthusiasts are too focused on images and need to show that fractal geometry can prove theorems (third through last sentences)
    • Comparison, according to the fractal skeptics:
      • Pre-fractal math has proven many theorems about fractals, but fractal geometry has only proven a few theorems that couldn't have been proven without fractals (fourth sentence) and only a few have been demonstrated
    • Author's attitude: "captivated" (first sentence); "astonishing" (first sentence)

Main Point: The ability of fractal geometry to generate complex patterns from simple processes has captivated the public and some practitioners, but others are skeptical that it can be used to prove theorems and thus have a lasting role in math.

Meta-Structure?

Describing a Debate: Even though the author doesn't bring up the debate until the last paragraph, this passage best fits the Describing a Debate Meta-Structure.* In such a passage, the author describes two sides of a debate without taking a side or attempting to reconcile the two sides. (If the author takes a side or attempts to resolve the debate, the passage is better understood as a "Resolving a Debate" passage.) In this passage, the author uses the first two paragraphs to explain the passage's subject matter (fractal geometry) before finally presenting the debate over that subject matter's usefulness. The author doesn't take sides in the debate beyond saying that the subject matter can produce some wild images.

In passages that utilize a Describing a Debate Meta-Structure, the main point generally describes both sides of the debate (or the assertion that there is a debate). We constructed our anticipated main point around both sides of the debate, while also including the public's fractal fascination for good measure.

*That said, we could call this an Old Approach/New Approach passage, with pre-fractal geometry as the old approach and fractal geometry as the new approach. That said, pre-fractal geometry doesn't play a huge factor in this passage, so we think this passage is better understood as a Describing a Debate passage.

Example: The passage dedicates a fair amount of real estate to the Koch curve example, making this example the most prominent minor Meta-Structure in the passage. This part of the passage describes the process by which that curve is generated and illustrates certain features of fractals (namely, self-similarity). The Koch curve is also discussed in the context of computer generation. This example is meant to explain to the reader what fractals are, and it's ancillary to the debate raised in the third paragraph, so it's more likely to show up as the topic for a few Minor Point, Application, or Argument Structure questions.

One more note about this example: the description of the Koch curve process is really hard to follow if you're not drawing it out. That doesn't mean you need to draw it out, as it's unlikely that there will be a lot of questions on it. But if you have the time, running through the relevant steps one or two times can be helpful for the questions that do involve the specifics!

Last Thoughts?

This passage's main point can trip up some test-takers. How come our anticipated main point only summarizes the third paragraph? Aren't main points supposed to be comprehensive and summarize the entire passage?

These are good questions and valid concerns! But it's important to remember that in Reading Comp, arguments are far more important to the passage than details. The first two paragraphs only include details. They describe what fractals are and how people generate them using computers. These details essentially provide background information on the passage's subject matter.

We don't get arguments until the third paragraph. Each side presents their argument on the utility of fractals. "Fractals are useful because they'll help mathematicians describe natural shapes easily." "Fractals are not yet useful because they don't support a system of theorems and proofs." These arguments feature details (the evidence both sides use), but they also feature conclusions — evidence-backed opinions that each side has about fractals. Much as we understand arguments through the conclusion in LR, we’ll understand passages through their conclusions in RC. These conclusions help identify what's really important in the passage. We'll use those conclusions to define the passage's Meta-Structure and main point.

Question prompt

Which one of the Remaining source text redacted.
Why the credited answer is right

Credited answer: C

The notes below walk through why it fits the stem and how to eliminate the rest.

Question Type

Science

Strategy Overview

Review the purpose of the paragraph in which the expression is found, including the expression in question, then use the purpose and the immediate context to define the expression's meaning

Answer Anticipation

This question asks what the author meant when they used the phrase "fully explicit." This phrase appeared in the second paragraph, so we should start by defining the role of that paragraph, as that can sometimes provide contextual clues about the author's meaning. Our note for the second paragraph is, "Use of computers in fractal geometry (not limited by what can be drawn/displayed, so can create more complex fractals)." Nothing in that note seems to relate to the phrase "fully explicit," so our note won't provide contextual clues in this case.Now, turning our attention to the expression in question, the sentence starts with, "Since," telling us that it's a premise supporting an argument in the latter half of the sentence. So, let's break this down like an LR question! The premise asserts that the steps to generate the Koch curve are (1) "fully explicit" and (2) always the same (P2, S2). From these premises, the author draws a conclusion that the Koch curve can be generated by a computer (P2, S2).So, the two elements noted — fully explicit, always the same — are what allow a computer to generate the Koch curve. What would need to be true for that to make sense? Well, computers can't make a judgment call at all, so they need to receive instructions to do what they do. The second half of the premise establishes that the computer is simply repeating a step, so the first half must be what establishes that the instructions aren't relying on a judgment call from the computer — that a "fully explicit" instruction provides a complete and clear description of what has to be done in a way that a computer can understand.That makes sense in the context of the passage. Importantly, it also aligns with the common definition of the phrase in question, as "fully explicit" means that it's stated completely and clearly. Let's find an answer reflecting this.

Answer choices

  1. A
    illustrated by an example
    Why choice A is not credited

    (A) Does this say that "fully explicit" means the description is stated "completely and clearly"?

    No. So, let's eliminate (A). The Koch curve is an example of a fractal, but it doesn't make sense to say that a computer can generate it because the rules for generating it are "illustrated by an example." That's not related to the phrase "fully explicit," and an example would probably help a human more than a computer!

  2. B
    uncomplicated
    Why choice B is not credited

    (B) Does this say that "fully explicit" means the description is stated "completely and clearly"?

    Nope. So, let's eliminate (B). Still, this is a tempting answer to many, as the author does claim that fractal geometry is attractive because simple processes can lead to incredibly complex patterns, defining the processes as uncomplicated (P2, S4). However, that's way down at the bottom of the second paragraph, not up where "fully explicit" is noted, and there's no indication that a computer needs a process to be uncomplicated to follow it!

    Finally, "uncomplicated" is not a valid synonym for "explicit." "Uncomplicated" means something is simple or easy, while "explicit" means something is clear or unambiguous. These words might be used to describe the same thing, but they do not necessarily mean the same thing.

  3. C
    expressed unambiguously
    Why choice C matches the stem

    (C) Does this say that "fully explicit" means the description is stated "completely and clearly"?

    Yes! This matches our anticipation, so we can select (C) and move on. After all, the phrase in question is a part of the premises supporting a conclusion that a computer can generate the Koch curve (P2, S2). Since computers just follow directions and can't make judgment calls, any rules they follow would need to be "expressed unambiguously," as this answer states. "Unambiguous" is also a valid synonym of "explicit," so this is the correct answer.

  4. D
    in need of lengthy Remaining source text redacted.
    Why choice D is not credited

    (D) Does this say that "fully explicit" means the description is stated "completely and clearly"?

    Nope. So, let's eliminate (D). The author does note in the following sentence that the Koch curve is the result of infinitely many steps (P2, S3). However, the author uses that sentence to contrast the theoretical and practical process of generating the Koch curve. Therefore, that sentence isn't used to clarify the previous sentence, which describes the steps for generating the Koch curve.

    Moreover (and perhaps more to the point), "in need of length computation" is not a valid synonym for "explicit." "Explicit" (at least when we're not talking about naughty language or images) means something is clear or unambiguous.

  5. E
    agreed on by all
    Why choice E is not credited

    (E) Does this say that "fully explicit" means the description is stated "completely and clearly"?

    No. So, let's eliminate (E). After all, the phrase in question is a part of the premises supporting a conclusion that a computer can generate the Koch curve (P2, S2). Not everyone would have to agree to the rules for the Koch curve for it to be drawn by a computer.

    Moreover (and perhaps more to the point), "agreed on by all" is not a valid synonym for "explicit." "Explicit" means something is clear or unambiguous, not that people agree with the statement. We could use both phrases to describe the same thing (e.g., the rules of chess are explicit and agreed upon), but they do not necessarily mean the same thing.

What this tests

Question analytics

Based on historical answer selection rates for this question.

Answer choice distribution

  1. A 7%
  2. B 11%
  3. C Credited 74%
  4. D 2%
  5. E 7%

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