Country B's oil production is not sufficient to meet its domestic dema

Question

Country B's oil production is not sufficient to meet its domestic demand .In order to sharply reduce its dependence on foreign sources of oil, Country B recently embarked on a program requiring all of its automobiles to run on ethanol in addition to gasoline. Combined with its oil production, Country B produces enough ethanol from agricultural by-products to meet its current demand for energy.

Which of the following must be assumed in order to conclude that Country B will succeed in its plan to reduce its dependence on foreign oil?

(A) Electric power is not a superior alternative to ethanol in supplementing automobile gasoline consumption.

(B) In Country B, domestic production of ethanol is increasing more quickly than domestic oil production.

(C) Ethanol is suitable for the heating of homes and other applications aside from automobiles.

(D) In Country B, gasoline consumption is not increasing at a substantially higher rate than domestic oil and ethanol production.

(E) Ethanol is as efficient as gasoline in terms of mileage per gallon when used as fuel for automobiles.

Source: MGMAT 4th Edition

parker · Accepted Answer

Good question to use for practice with zooming in on the exact scope of the conclusion.

Country B’s goal is to REDUCE DEPENDENCE ON FOREIGN OIL. The way it plans to do this is by requiring cars to run on ethanol as well as gas. With topics such as this one, which are often in the news, it’s tempting to bring in a whole string of assumptions that we know from the real world, but be vigiliant! You can only use the information that you have in the argument.

(A) Whether something else is superior does not affect whether ethanol would or would not help reduce the amount of gasoline (and therefore imported oil) needed. Eliminate.

(B) The relative rates of production of each material don’t matter—and we already know that we have a domestic oil deficit, bc we have to import oil! Eliminate.

(C) Whether Ethanol can be used in other ways doesn’t matter—we just want to help support the claim that mandating ethanol in cars will reduce foreign oil dependence. “Reduce” is a very clear-cut term—if we reduced the imported oil by one drop, that would still count. So while using ethanol for many other things might help with the scale of imported fuel reduced, that scale does not matter…we just want to help prove we would need at least one drop less. Eliminate.

(D) Any time you see a “not” thrown in there, it can make it harder to figure out what the thought really is. That is a deliberate move on the part of the test-writers. Having already eliminated A-C, this would be a safe place to use the negation test, to help unravel the meaning of this choice(do NOT use this test on every answer choice, as it will take way too long).

If gas consumption IS increasing at a substantially higher rate than domestic oil and ethanol production, that means that we would need more gas (and that gas would need to come from imported oil). If that is the case, then even mandating ethanol use in cars would not be sufficient to meet this substantial increased need, and therefore foreign oil dependence would NOT decrease. This is likely our answer.

(E) The relative efficiency of ethanol versus gas doesn’t matter—we care about reducing oil dependence. This is a “helpful” assumption, but not a necessary one. It’s great that ethanol is as efficient as gas (and by extension, that we could replace gas with ethanol in a one-to-one ratio) but even if it were only half as efficient, we could still produce 2x the amount of ethanol and reach our goal of reducing foreign oil dependence. Eliminate.

Skywalker18 · Answer

Country B's oil production is not sufficient to meet its domestic demand. In order to sharply reduce its dependence on foreign sources of oil, Country B recently embarked on a program requiring all of its automobiles to run on ethanol in addition to gasoline. Combined with its oil production, Country B produces enough ethanol from agricultural by-products to meet its current demand for energy.

Type - Assumption
Boil it down - Combined with its oil production, Country B produces enough ethanol from agricultural by-products to meet its current demand for energy.

A. Electric power is not a superior alternative to ethanol in supplementing automobile gasoline consumption. - Out of scope

B. In Country B, domestic production of ethanol is increasing more quickly than domestic oil production. -Irrelevant- as long as B can use both of them to meet domestic demand all is well .

C. Ethanol is suitable for the heating of homes and other applications aside from automobiles. - Irrelevant

D. In Country B, gasoline consumption is not increasing at a substantially higher rate than domestic oil and ethanol production.- Correct - on negation this breaks the argument . If rate of gasoline consumption is substantially higher than domestic oil and ethanol production , then the conclusion will fall apart .

E. Ethanol is as efficient as gasoline in terms of mileage per gallon when used as fuel for automobiles. Irrelevant - Efficiency is not our concern

Answer D

bestgmat · Answer

Alright, let's dissect this situation. Country B wants to use ethanol as an alternative to foreign oil. The passage tells us they've got enough ethanol from agricultural by-products to meet their current energy demand. The goal is to see under what conditions this plan might succeed.

Here’s the plan, in simple terms: "We don’t have enough oil. Let's use our ethanol (which we have enough of) in cars to reduce how much foreign oil we need."

Now, let's evaluate our answer choices:

This choice relates to another alternative (electricity), but the passage focuses on ethanol. Even if electricity was superior, it wouldn’t directly impact the ethanol plan.

While this is a positive sign for the plan, it's not critical. The passage already tells us that they produce enough ethanol to meet current demand. It doesn't rely on the growth rate.

This talks about other uses of ethanol, but the passage specifically discusses using ethanol for automobiles. We're not concerned with other applications here.

Now, this is important! If gasoline consumption rapidly increases and surpasses the combined production of domestic oil and ethanol, then Country B would still depend on foreign oil. This assumption is vital for the plan to work.

While efficiency is a concern for consumers, this doesn’t directly impact the country's dependence on foreign oil. Even if ethanol was less efficient, the main goal is to replace foreign oil, not to ensure efficiency.
Therefore, the most crucial assumption to ensure Country B's success in reducing dependence on foreign oil is:

(D) In Country B, gasoline consumption is not increasing at a substantially higher rate than domestic oil and ethanol production.

I hope that clears things up! The future of Country B's energy seems intriguing! 🚗💨🌽

gamebird96 · Answer

I still have doubts with option C, the goal is to reduce foreign oil dependence, and to do so they want to blend G+E, and all automobile to use that.
Now I do agree with D, but if other things that generally rely on G cannot use G+E blend, then it still has to import Oil and the dependence won’t reduce. Isn’t that still an assumption?

guddo · Answer

Not quite. (C) would matter if the conclusion were that Country B will  eliminate  all foreign oil dependence or replace oil in every use.

But the plan described is narrower: automobiles must use ethanol in addition to gasoline. So the intended reduction comes from cutting gasoline use in cars.

Even if ethanol cannot be used for home heating or other applications, Country B can still reduce foreign oil dependence by replacing some automobile gasoline with ethanol.

(D) is necessary because if gasoline demand keeps rising much faster than domestic oil plus ethanol production, then the ethanol program may not reduce dependence at all.

So (C) is useful only for a stronger conclusion. For this conclusion, it is  not required .

Country B's oil production is not sufficient to meet its domestic dema

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Country B's oil production is not sufficient to meet its domestic dema

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