Because of a technological breakthrough, all gas heating furnaces

Question

Because of a technological breakthrough, all gas heating furnaces produced from next year on will be significantly more efficient than those currently in use in Verania. Accordingly, it can be expected that, as older furnaces are replaced with new ones, the amount of gas consumed annually per household in Verania will decrease significantly.

Which of the following, if true of Verania, most weakens the case for the claim made?

(A) In many cases, households use the same furnace for 20 years or more.

(B) Because of environmental concerns, most people would prefer not to use fossil fuels such as gas.

(C) Currently, most households set their thermostats at uncomfortably low temperatures because of the high cost of heating their houses.

(D) An increasing number of households are replacing their gas heating systems with systems that use geothermal energy.

(E) The difference in efficiency between older gas furnaces and ones that use the new technology is unlikely to cause many people to replace their furnaces.

Source:  Marty Murray Coaching

MartyMurray · Accepted Answer

Because of a technological breakthrough, all gas heating furnaces produced from next year on will be significantly more efficient than those currently in use in Verania. Accordingly, it can be expected that, as older furnaces are replaced with new ones, the amount of gas consumed annually per household in Verania will decrease significantly.

The conclusion of the argument is the following:

it can be expected that, as older furnaces are replaced with new ones, the amount of gas consumed annually per household in Verania will decrease significantly

The support for the conclusion is the following:

all gas heating furnaces produced from next year on will be significantly more efficient than those currently in use in Verania

We see that the reasoning of the argument is basically that, since new furnaces will be more efficient than those currently in use, as the furnaces currently in use are replaced with new ones, the average amount of gas consumed by a household will decrease.

Which of the following, if true of Verania, most weakens the case for the claim made?

This is a Weaken question, and the correct answer will weaken the case for the conclusion. In other words, it will show that, even though new furnaces are more efficient than the ones currently in use, the replacement of older furnaces with new ones may not result in a decrease in the amount of gas used.

(A) In many cases, households use the same furnace for 20 years or more.

This choice is tricky to eliminate because it indicates that furnaces may not be replaced for quite some time. So, it could seem to indicate that the amount of gas used per household won't decrease.

Here's the thing though.

The point of the argument is not that furnaces will be quickly replaced. It's that AS they are replaced, the amount of gas used will decrease.

So, the conclusion could be true regardless of whether furnaces are replaced soon or 20 years in the future. Either way, as they are replaced, the amount of gas used could decrease.

So, this choice has no effect on the strength of the argument.

Eliminate.

(B) Because of environmental concerns, most people would prefer not to use fossil fuels such as gas.

If anything, this choice strengthens, rather than weakens, the argument.

After all, if people would prefer not to use gas, then we have even more reason to believe that the amount of gas used per household will decrease because people will seek to achieve what they prefer, which is reduced use of gas.

Eliminate.

(C) Currently, most households set their thermostats at uncomfortably low temperatures because of the high cost of heating their houses.

This choice is interesting.

If, "currently, most households set their thermostats at uncomfortably low temperatures because of the high cost of heating their houses," then, when people get new, more efficient furnaces, there's a good chance that they'll take advantage of the savings provided by the efficiency and set their thermostats at higher, more comfortable temperatures.

So, replacement of furnaces with new ones may not result in a decrease in gas use because, even though the new furnaces will be more efficient, people may offset that increased efficiency with greater use of the furnaces. After all, with more efficient furnaces, they can be more comfortable while spending the same amount of money on gas.

So, this choice indicates that, even though new furnaces are more efficient, it may not be the case that, as furnaces currently in use are replaced with new ones, gas use will decrease.

Thus, it weakens the case for the conclusion.

Keep.

(D) An increasing number of households are replacing their gas heating systems with systems that use geothermal energy.

Although this choice is not about replacing gas furnaces with new ones, it does provide a reason to believe that the amount of gas used per household will decrease in the future.

So, in a way, this choice strengthens, rather than weakens, the case for the conclusion that, as older furnaces are replaced with new ones, the amount of gas consumed annually per household.

After all, the future is when older furnaces will be replaced. So, any reason to believe that gas use will decrease in the future helps to confirm the conclusion.

Eliminate.

(E) The difference in efficiency between older gas furnaces and ones that use the new technology is unlikely to cause many people to replace their furnaces.

This choice is tricky to eliminate because it could seem to indicate that new furnaces are not much more efficient than the ones currently in use and also that people won't replace their furnaces with new ones.

So, to eliminate this choice, we have to see that, regardless of what this choice says, the passage states as fact that "all gas heating furnaces produced from next year on will be  significantly  more efficient than those currently in use."

So, even if the difference in efficiency is "unlikely to cause many people to replace their furnaces," according to the passage, it is significant. Thus, as people replace their furnaces, they may use less gas.

Furthermore, while this choice may indicate that furnaces may not be replaced quickly, the point of the argument is not that furnaces will be quickly replaced. It's that, AS they are replaced, soon or far in the future, the amount of gas used will decrease.

So, this choice has no effect on the strength of the argument.

Eliminate.

Correct answer:   C

kayarat600 · Answer

I was confused between the two options too but I'm gonna be honest despite the tutors explanation it's just not convincing c is a this might maybe lead to more usage it's possible but e explicitly says nah they w9nt adopt it because they don't feel like it's worth it

The furthermore it might not be replaced early thing works for another option but it has no purpose here imo.

If the questions are going to be this weird I'm not sure I have anything but luck that could help me.

This significantly weakens the whole purpose of the new technology.

The person infm the article believes something to be true because of x. But the option says these people don't put weight on x and hence this plan d0esnt appeal to them this option is too logical to discount someone help me put here.

MartyMurray · Answer

To get Critical Reasoning questions correct, we have to pay careful attention to the conclusion.

In this case, the conclusion is the following:

it can be expected that, as older furnaces are replaced with new ones, the amount of gas consumed annually per household in Verania will decrease significantly

Notice that the author does not indicate anything about WHEN or WHY furnaces will be replaced. The only point is that, AS furnaces are replaced, households will use less gas.

Now, let's consider choice (E).

(E) The difference in efficiency between older gas furnaces and ones that use the new technology is unlikely to cause many people to replace their furnaces.

All this choice indicates is that the difference in efficiency will not CAUSE people to replace their furnaces.

So, even if this choice is true, it is still the case that, as people replace furnaces over time for whatever reason, they will reduce their use of gas.

In other words, (E) weakens the case for the wrong conclusion.

So, it's not the correct answer.

Takeaway:  When answering a Weaken question, carefully note the conclusion and ensure that the answer you choose casts doubt on that conclusion rather than on a related, but different, conclusion.

Vishnu0001 · Answer

Don't think this is a 705-805 level question..

djangobackend · Answer

Hi  MartyMurray ,  ChiranjeevSingh   KarishmaB   GMATNinja  I have a doubt in this question. 
as the argument says "as older furnaces are replaced with new ones" say X happens then Y (the amount of gas consumed annually per household in Verania will decrease significantly) will happen. now my thinking to reject A,B, and E was that we do not care if X happens in the first place or not OR we do not care IF X happens or not. We should only be concerned that IF X happens then does Y happen? and since A,B,E plays on the fact whether X will happen or not hence I rejected it. 
does it make sense? or my analysis is wrong? 
while I believe C is the clear answer since it "suggests" that their consumption can increase.

Thanks for the help!!

MartyMurray · Answer

Yes, exactly. Your analysis of that aspect of the argument is spot on.
 
That makes sense as well, though (B) is a little different from the others. (B) provides some support for the conclusion by providing an additional reason to believe that gas consumption will decrease over time.
 
Indeed, that's why (C) is correct.

Nice work.

Because of a technological breakthrough, all gas heating furnaces

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GMAT Critical Reasoning (CR) Questions

Because of a technological breakthrough, all gas heating furnaces

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