LSAT 104 | Section 4 | Logical Reasoning: Q9

LR Question 9 Explanation

QUESTION TEXT: The only physical factor preventing a human journey to Mars has…

QUESTION TYPE: Necessary Assumption

CONCLUSION: We can go to Mars, and come back.

REASONING: A new device lets a spaceship refuel on Mars. Previously, a spacecraft with enough fuel to return from Mars would have been to heavy to launch.

ANALYSIS: The argument is assuming we can launch a spacecraft with enough fuel to return from Mars.

___________

1. It doesn’t matter how much fuel is needed to return, as long as this device lets us make it on Mars.
2. The fuel’s composition doesn’t matter, as long as it works.
3. I’m sure the crew can give up a little living space. As long as there’s enough space for the device and the crew, everything will work out.
4. The argument didn’t say we should go to Mars, or that it would be cheap to go there. The author just said it’s now possible.
5. CORRECT. The fuel tanks were too heavy, so the device will also be too heavy if it weighs more than the fuel tanks it is replacing.

Recap: The question begins with “The only physical factor preventing a human journey to Mars has”. It is a Necessary Assumption question. Learn how to master LSAT Necessary questions on the LSAT Logical Reasoning question types page.