LR Question 6 Explanation
QUESTION TEXT: The largest volcano on Mars rises 27 kilometers above…
QUESTION TYPE: Must be True
FACTS:
- Mars has a really, really big volcano.
- Earth couldn’t have a volcano that big, even if Earth’s gravity were low like Mars’ gravity.
- Earth’s crust is too thin, and the volcano would sink.
ANALYSIS: We know that Mars has a thicker crust, at least in some spots. Otherwise, the volcano would sink.
___________
- We’re not told anything about erosion. We have no idea why Mars has a thicker crust.
- Who knows? Mars’ crust might be thick enough to support big volcanoes in many places.
- We know one Martian volcano is really tall. But maybe most Martian volcanoes are tiny, and they drag down the overall average.
- CORRECT. Mars’ crust has to be thicker at least at the place where the giant volcano is. Otherwise the volcano would sink.
- Who knows? There may be many factors apart from crust thickness that determine how big a volcano will be.
Recap: The question begins with “The largest volcano on Mars rises 27 kilometers above”. It is a Must be True question. Learn more about LSAT MBT questions in our guide to LSAT Logical Reasoning question types.
More Resources for Must Be True Questions
- Conditional Reasoning Article: Learn about conditional statements on the LSAT.
- LR Diagrams Guide: Learn how to draw LR diagrams.
- Intro to Conditional Reasoning: This intro course lesson covers conditional reasoning basics.
- Intro Course lesson: This intro course lesson covers Must Be True questions.
- Mastery Seminar lesson: This LR Mastery seminar lesson covers must be true questions.
The Reason I didn’t pic this answer was because the fact that Mars has low gravity, this made the idea realistic that even if Mars also has a thin crust, as does Earth, the mass of the mountain wouldn’t affect it because of the low gravity. Earth has a thin crust and we can infer from the passage that earth also has a higher gravity than Mars.
We know of two differences between Mars and Earth: gravity and thickness of crust. The second sentence says even if Earth’s gravity was as low as Mars’, such a big volcano still couldn’t exist, BECAUSE Earth’s crust is too thin. So that directly tells us that it’s due to the thickness of the crust. Hope that helps!