Balzania put in place regulations

[singh.181]

Twenty years ago, Balzania put in place regulations requiring operators of surface mines to pay for the reclamation of mined-out land. Since then, reclamation technology has not improved. Yet, the average reclamation cost for a surface coal mine being reclaimed today is only four dollars per ton of coal that the mine produced, less than half what it cost to reclaim surface mines in the years immediately after the regulations took effect.

Which of the following, if true, most helps to account for the drop in reclamation costs described?

A. Even after Balzania began requiring surface mine operators to pay reclamation costs, coal mines in Balzania continued to be less expensive to operate than coal mines in almost any other country.
B. In the twenty years since the regulations took effect, the use of coal as a fuel has declined from the level it was at in the previous twenty years.
C. Mine operators have generally ceased surface mining in the mountainous areas of Balzania because reclamation costs per ton of coal produced are particularly high for mines in such areas.
D. Even after Balzania began requiring surface mine operators to pay reclamation costs, surface mines continued to produce coal at a lower total cost than underground mines.
E. As compared to twenty years ago, a greater percentage of the coal mined in Balzania today comes from surface mines.

Confused between B and C. Here is my analysis:

What is Happening:
Operators must the reclamation cost, and reclamation technologu has not improved.

Normally this would mean:
reclamation cost should go up.

Instead this happening:
drop in reclamation costs.

B: demand of coal has dropped resulting in less mining, so drop in reclamation costs.
C: makes sense, if I consider the average reclamation cost.

OA C
Please suggest.

[jnelson0612]

Overall I like what you are saying. I would describe the discrepancy as this:

In the time since the reclamation regulations were put in place, the average reclamation cost of a coal mine has gone down, even though there has been no improvement in technology. How can this be?

Possible reason: Even though technology has not improved, some other factor has changed that permits less costly reclamation.

C gives us a strong reason why reclamation has gotten cheaper. The nature of the mines has changed, making it less difficult to reclaim them.

B looks good EXCEPT look very carefully at the wording of the argument. It says "average cost of a coal mine". Creating fewer coal mines does not matter to this argument, because it is average cost PER mine reclaimed that we are concerned about. Make more sense?

[iharden]

Could the answer also not be "B" because it addresses the use of coal as fuel, and not the relationship of reclamation and coal?

The reason I didn't choose "C" is because it specifies the "mountainous areas" and reiterates ..."In such areas." The stimulus never mentions these particular areas. When do you know to take that leap in logic?

[violetwind]

Overall I like what you are saying. I would describe the discrepancy as this:

In the time since the reclamation regulations were put in place, the average reclamation cost of a coal mine has gone down, even though there has been no improvement in technology. How can this be?

Possible reason: Even though technology has not improved, some other factor has changed that permits less costly reclamation.

C gives us a strong reason why reclamation has gotten cheaper. The nature of the mines has changed, making it less difficult to reclaim them.

B looks good EXCEPT look very carefully at the wording of the argument. It says "average cost of a coal mine". Creating fewer coal mines does not matter to this argument, because it is average cost PER mine reclaimed that we are concerned about. Make more sense?

I don't get this explanation at all.....it seems that it doesn't match this CR problem, neither for C nor for B....

Could any instructor see this again?

I'm also confused about B, though I guess C is better.

B says that the demand for coal as fuel is declining, which could affect the business performance of B's coal mines and therefore could make the owners of the coal mines lower the price of reclamation cost.

C says that people don't like to go mining at B because of the high price of reclamation cost. This is also a reason that could make the owners of the coal mines to lower the price in order to attract more business.

Therefore it seems both B and C give reasons from a same perspective, and C is a little closer to the issue at hand.

Is it how we eliminate B?

[cseramit]

Overall I like what you are saying. I would describe the discrepancy as this:

In the time since the reclamation regulations were put in place, the average reclamation cost of a coal mine has gone down, even though there has been no improvement in technology. How can this be?

Possible reason: Even though technology has not improved, some other factor has changed that permits less costly reclamation.

C gives us a strong reason why reclamation has gotten cheaper. The nature of the mines has changed, making it less difficult to reclaim them.

B looks good EXCEPT look very carefully at the wording of the argument. It says "average cost of a coal mine". Creating fewer coal mines does not matter to this argument, because it is average cost PER mine reclaimed that we are concerned about. Make more sense?

I don't get this explanation at all.....it seems that it doesn't match this CR problem, neither for C nor for B....

Could any instructor see this again?

I'm also confused about B, though I guess C is better.

B says that the demand for coal as fuel is declining, which could affect the business performance of B's coal mines and therefore could make the owners of the coal mines lower the price of reclamation cost.

C says that people don't like to go mining at B because of the high price of reclamation cost. This is also a reason that could make the owners of the coal mines to lower the price in order to attract more business.

Therefore it seems both B and C give reasons from a same perspective, and C is a little closer to the issue at hand.

Is it how we eliminate B?

@violetwind

Option B:-
Lower Demand -> Lower Mining of Coal , Lesser reclamation of land.
Overall Cost for Land reclamation would be lesser. But question is about the AVERAGE cost of reclamation of land.

[RonPurewal]

B says that the demand for coal as fuel is declining, which could affect the business performance of B's coal mines and therefore could make the owners of the coal mines lower the price of reclamation cost.

C says that people don't like to go mining at B because of the high price of reclamation cost. This is also a reason that could make the owners of the coal mines to lower the price in order to attract more business.

no, jamie's (jnelson) explanation is correct. i think the problem is that you don't understand what "reclamation" is; this issue is clear from your portrayal of reclamation has something whose cost can be controlled at will by business owners.

"reclamation" refers to the action of taking land that has been strip-mined, or destroyed in some other way, and making it serviceable again for purposes such as agriculture. this is not a cost that can be changed at will by businesspeople. (as an analogy, consider "the cost of extracting petroleum from the ground"; that is another cost that is a function of environmental factors and external costs, not something that businesspeople can manipulate.)

[violetwind]

B says that the demand for coal as fuel is declining, which could affect the business performance of B's coal mines and therefore could make the owners of the coal mines lower the price of reclamation cost.

C says that people don't like to go mining at B because of the high price of reclamation cost. This is also a reason that could make the owners of the coal mines to lower the price in order to attract more business.

no, jamie's (jnelson) explanation is correct. i think the problem is that you don't understand what "reclamation" is; this issue is clear from your portrayal of reclamation has something whose cost can be controlled at will by business owners.

"reclamation" refers to the action of taking land that has been strip-mined, or destroyed in some other way, and making it serviceable again for purposes such as agriculture. this is not a cost that can be changed at will by businesspeople. (as an analogy, consider "the cost of extracting petroleum from the ground"; that is another cost that is a function of environmental factors and external costs, not something that businesspeople can manipulate.)

Totally undersand this problem this time! Thanks Ron and Jamie!

I thought I was a little bit misled by the first sentence of the argument ----goverment began to require the miner to pay for the reclamation fee. After reading it, I thought the level of reclamation fee was kind of government-controlled.(I mean, the government can decide wether or not to give some fiscal subsidy for reclamation depending on the market situation of mining industry~~) but my focus was totally diverted.....

And I also had a big self-made presumtion in my head last time I read this argument----I thought mines are all in the mountainous area!!! Therefore, I totally couldn't get what Jamie said by "nature of the mines"~~~

Though I've been reminding myself this kind of fallacy all the time~~~ it seems that I need to watch out these hidden walls in my mind more cautiously to crack CR! :-)

Sorry Jamie and thank you very much~

Thanks very much too, Ron.

[RonPurewal]

giad that the discussion helped.

[pratik.munjal]

There is one problem I still have-

c) says that the activities have reduced in the mountainous regions. That limits the scope to mountainous regions only.

So does that not limit the scope? In other words, doesn't that make b a better choice?

[RonPurewal]

There is one problem I still have-

c) says that the activities have reduced in the mountainous regions. That limits the scope to mountainous regions only.

still affects the overall average for all mining operations. you can't have a situation in which changing a component doesn't change the average!

[davetzulin]

Hi Ron, just watched your video on this question

question excerpt

four dollars per ton of coal that the mine produced

i guess we have to assume that damage incurred on the surface area is in direct relation with each ton of coal mined? more mining, more reclamation cost?

I had a somewhat stupid thought that the cost of reclamation HAPPENED to be $4/ton of coal. Meaning the cost of reclamation of land ABC is a flat $100. Operator of mine ABC happened to mine 25 tons for coal, therefore $4/ton of coal. Another mine XYZ could be $50 flat for reclamation.

so if you were to increase the amount of coal mined, now you're paying less per ton of coal. E caught my eye, but then again it is a percentage so actual coal mined does not have to increase i guess.

E. As compared to twenty years ago, a greater percentage of the coal mined in Balzania today comes from surface mines.

i have no argument with answer choice C, it looks completely correct now. Lately I have been doing tricky problems of all types and unfortunately I feel compelled to look for the least obvious (most tricky) explanation . Then I pre-phrased, "coal must go up", and eliminated C without even reading the 2nd half.

*edit, if this answer choice exists then these test makers must have knew someone would fall for that line of reasoning right?

[RonPurewal]

more mining, more reclamation cost?

these problems do require a certain baseline amount of common sense, yes.
note that the common-sense component really *is* "common": if the test writers wrote a problem that they thought involved common sense, but the problem in fact confused test takers, then it would be rejected during the experimental phase.

Lately I have been doing tricky problems of all types and unfortunately I feel compelled to look for the least obvious (most tricky) explanation .

this probably means that you've been doing problems from questionable third-party sources. (remember, documents downloaded for free are worth exactly what you pay for them!)

CR problems are not supposed to be "tricky". they are meant to challenge overly rigid modes of thinking, but they are not meant to stick a metaphorical foot out and trip you.

[benkriger]

Ron: Please let me know if my reasoning is ok for GMAT test day:

-The prompt states that the average cost is less today than when rule first stared

-Choice C: Only mines with low reclamation cost are being used now

-Therefore, choice C is right, because a change in the set of items, will readjust the average

Thank you in advance, if you get around to this.

[aliassad]

Yes. This is correct. You can get more intuitive understanding if you understand the logical structure of this particular CR. The action here revolves around "survivorship bias". This means the fittest survive and their average will be "better" than the previous average .

Analogy
So say you are averaging the batting averages of 100 players and you will select the top ten out of them. Then the batting averages of the top ten players will obviously be better.


The survivor ship bias is also tested in other offical questions though I cannot recall them at the moment.


Ali Asad

[RonPurewal]

ali,

i wouldn't recommend giving unnecessary names (like "survivorship bias" or whatever) to certain types of arguments. the net effect of doing that sort of thing, in the long run, will be to decrease your intuitive participation in the argument and to push you toward "rules"-based thinking (which won't work on cr).

So say you are averaging the batting averages of 100 players and you will select the top ten out of them. Then the batting averages of the top ten players will obviously be better.

this analogy basically works, but it's way too explicit (and therefore too obvious). specifically, you are actually saying that we are directly picking the best batting averages.

if you see this kind of thing in an argument, it will not be this direct. i.e., rather than explicitly saying that we're going to select the highest batting averages, the argument would be much more likely to include something that strongly implies, but doesn't actually state, that sort of preferential choosing.
for instance, if you are looking at the batting averages of players who have been in the major leagues for 15 years or more, then that's likely to produce the same sort of bias; that's an uncommonly long career length for a professional athlete, after all, so it's reasonable to anticipate that players with careers that long would have better statistics than average players would.

i think i remember a problem from the official guide that did this sort of thing (maybe it was gmat prep, i don't really remember). in any case, the problem basically contains the idea that century-old hotels all seem to have really good carpentry work. to figure out what's going on, you need to use the idea that any building still standing after 100 years was, most likely, uncommonly well built in the first place.