Logical reasoning PrepTest 105 · Section 2 · Question 24

Question prompt

Each December 31 in Remaining source text redacted.
Why the credited answer is right

Credited answer: B

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

Argument or Facts

Facts

Valid or Flawed

NA

Question Type

Must Be True Questions

Stimulus Summary

Each year, Country Q counts up the available coal supply (total coal mined - coal consumed) Since 1970 - No coal imported or exported 1990 - Coal supply was at a certain level 1991 - Coal supply was at a much lower level

Answer Anticipation

This Must be True question falls into a common pattern - a situation with some relative numbers (“considerably lower”) are thrown out there, and we’re meant to fill in some missing boxes with information that can be inferred. Here, we’re talking coal supply. Country Q has a much larger supply in 1990 than in 1991. And since no imports or exports occurred that year, the difference must be related to what was mined and what was used. The coal supply went down in ‘91 after being at a certain level in ‘90. In order for it to go down, they must have used more than they mined. Let’s find an answer reflecting that.

Answer choices

  1. A
    In Country Q, more Remaining source text redacted.
    Why choice A is not credited
    For the supply to go down, more coal must have been used than mined. There could have been more coal mined in ‘91 compared to ‘90 if use also skyrocketed. As such, we can’t infer this answer.
  2. B
    In Country Q, the Remaining source text redacted.
    Why choice B matches the stem
    For the overall supply of coal to go down, more would have to be used than mined. Since the overall supply declined in ‘91, Q must have used more coal that year than they mined. This is therefore the correct answer.
  3. C
    In Country Q, the Remaining source text redacted.
    Why choice C is not credited
    We don’t know if coal went down in ‘90 compared to ‘89, so we don’t know if consumption was particularly high in ‘90. Additionally, like (A), it’s not the consumption or the mining that we can draw inferences about, but the relationship between the two. Consumption could be higher in a year where the supply grows as long as mining is up!
  4. D
    In Country Q, the Remaining source text redacted.
    Why choice D is not credited
    This answer is the flip of answer (C), and it’s wrong for much the same reason. Consumption could be low in a year where the supply shrinks if mining levels are also pretty low.
  5. E
    In Country Q, more Remaining source text redacted.
    Why choice E is not credited
    Q looks only at the full year, so this answer about only the first half of the years is something we can’t infer.

What this tests

Question analytics

Based on historical answer selection rates for this question.

Answer choice distribution

  1. A 19%
  2. B Credited 42%
  3. C 9%
  4. D 27%
  5. E 3%

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