LSAT 152 | Section 2 | Logical Reasoning: Q7

LR Question 7 Explanation

QUESTION TEXT: Economist: ChesChem, a chemical manufacturer located…

QUESTION TYPE: Necessary Assumption

CONCLUSION: If natural gas prices go up in Chester even a tiny amount, ChesChem will move to Tilsen.

REASONING: If natural gas prices in Chester are more than double those in Tilsen, ChesChem will move. Currently prices are exactly double.

ANALYSIS: This is an algebra problem in disguise. There are two parts to the equation. Chester prices and Tilsen prices. The economist forgets that prices could rise in both cities at once. If so, we might have a price rise in Chester, and yet prices would still only be double or less.

E.g. Original prices: Chester 10, Tilsen 5

New prices: Chester 12, Tilsen 6

In both cases the Chester/Tilsen price ratio is 2.

(Algebra formula, for nerds: Chester price/Tilsen Price = Chester/Tilsen ratio)

Note that while I added negations below some wrong answers on this question, they’re really not what is important. This question is technically a necessary assumption question, but what lets you solve it is the formula above. There’s only one known factor in ChesChem’s decision making: the gas cost ratio. Once you realize the ratio depends on Tilsen prices too, the question is simple. No need to overcomplicate things with negations where they aren’t necessary.

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1. We don’t care what ChesChem spends. All we care about is cause and effect. We’re told that if the Chester/Tilsen gas cost ratio increases, ChesChem will move. That’s the only thing we care about. Other than that, we don’t care if ChesChem spends money on natural gas, staplers or whiskey and gambling.
2. CORRECT. If the Tilsen price increases, then the ratio of prices natural gas prices between Chester and Tilsen might remain two or less.
   Negation: The Tilsen price may increase
3. This goes too far. The answer assumes ChesChem would only move if gas prices were so high that ChesChem literally made no profit. But that doesn’t follow: ChesChem might remain profitable, but conclude they’re spending too much on gas in Chester, and move anyway. No one likes wasting money for no good reason.
    
   (Further, profits were not a factor given in the stimulus)
   Negation: ChesChem might move even if still profitable.
4. The argument would actually be stronger if this wasn’t true! Negating this answer shows management has other reasons to consider a move, strengthening the idea that ChesChem would want to move if prices increase.
   Negation: If ChesChem moves, it will get many benefits from moving to Tilsen, besides lower gas prices.
5. This isn’t necessary. The author might be open to other reasons for moving. E.g. if there was an earthquake that destroyed Chester, the author might say “Yes, I suppose ChesChem would move their factory in that case too”.
    
   Our true concern here is what happens if natural gas prices rise. This answer is referring to what happens if gas prices don’t increase, which doesn’t matter.
   Negation: Cheschem may move even if natural gas prices do not increase.

Recap: The question begins with “Economist: ChesChem, a chemical manufacturer located”. It is a Necessary Assumption question. Learn how to master LSAT Necessary questions on the LSAT Logical Reasoning question types page.