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Having tough time with this one (Shelbyville)...Please help

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Having tough time with this one (Shelbyville)...Please help

by ssgmatter » Mon May 24, 2010 8:14 am
Guys can anyone please help me understand the logic on this one...I am really having a tough time with this CR

Last year all refuse collected by Shelbyville city services was incinerated. This
incineration generated a large quantity of residue ash. In order to reduce the amount
of residue ash Shelbyville generates this year to half of last year's total, the city has
revamped its collection program. This year city services will separate for recycling
enough refuse to reduce the number of truckloads of refuse to be incinerated to half
of last year's number.
Which of the following is required for the revamped collection program to achieve its
aim?
A. This year, no materials that city services could separate for recycling will be
incinerated.
B. Separating recyclable materials from materials to be incinerated will cost
Shelbyville less than half what it cost last year to dispose of the residue ash.
C. Refuse collected by city services will contain a larger proportion of recyclable
materials this year than it did last year.
D. The refuse incinerated this year will generate no more residue
ash per truckload incinerated than did the refuse incinerated last year.
E. The total quantity of refuse collected by Shelbyville city services this year will be
no greater than that collected last year.
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by asamaverick » Mon May 24, 2010 8:41 am
IMO it should be D.

The premise here is that the city services will try to separate enough refuse for recycling, so that the truckloads of refuse to be incinerated is reduced to half of previous year's number.

A : This goes on a totally different track. Why would you incinerate something that ought to be recycled?

B & C are irrelevant to the argument.

D : Yes this is a requirement. If the city service were to separate enough residue for recycling and reduce the truckloads of refuse that is to be incinerated to half, then it is important that each of the truckload generate no more residual ash than last year.

E : This is a good candidate for the answer. But the counter argument for this could be that, even if the total quantity of refuse were higher (than last year) the city service will attempt to separate enough for recycling so that the amount that is to be incinerated is still half of previous years number.
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by sk818020 » Mon May 24, 2010 8:44 am
IMO the answer is D.

The way I wrapped up the argument is;

Because they are seperating the refuse the number of truckloads of refuse this year will be half what it was last year.

D makes sense because otherwise the truckloads could result in higher concentrations of residue ash, which would not allow the author to come to the conclusion they did. If each truckload will result in the same amount of residue ash, then it is safe to conclude that there will be half as much residue ash, because your burning half as many truckloads of material.

What is the OA?

Hope that helps,

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by ssgmatter » Mon May 24, 2010 8:46 am
Is this assumption or strengthen type CR?

I will post the OA as the discussions progress.

I think I am more confused now...:(
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by kevincanspain » Mon May 24, 2010 9:08 am
You are asked for the assumption underlying the plan. Try to explain why you are confused so we can help!
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by sk818020 » Mon May 24, 2010 9:54 am
ssgmatter wrote:Is this assumption or strengthen type CR?

I will post the OA as the discussions progress.

I think I am more confused now...:(
I would classify this as an assumption question, because the question stem asks us what must be true for the program to achieve its goal. What unstated premise would, if stated, ensure that goal was met?
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by sk818020 » Mon May 24, 2010 9:57 am
sk818020 wrote: If each truckload will result in the same amount of residue ash, then it is safe to conclude that there will be half as much residue ash, because your burning half as many truckloads of material.
For a start, try to explain what it is about the sentence above that is confusing you. Or would you like another view why the other answers aren't correct. Let me know what direction to take and see what I can do.

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by diebeatsthegmat » Mon May 24, 2010 10:29 am
sk818020 wrote:IMO the answer is D.

The way I wrapped up the argument is;

Because they are seperating the refuse the number of truckloads of refuse this year will be half what it was last year.

D makes sense because otherwise the truckloads could result in higher concentrations of residue ash, which would not allow the author to come to the conclusion they did. If each truckload will result in the same amount of residue ash, then it is safe to conclude that there will be half as much residue ash, because your burning half as many truckloads of material.

What is the OA?

Hope that helps,

Jared
hi,
i still dont understand your explanation for the answer you chose. why the answer cant be C?
the argument says that the refused the city incinerated caused air pollution and its program is that it would seperate ash which could incinerate and which could be reproduced, rerecycled.
Thus, i give out the question whether the ash the city collected is rerecycled? what if it couldnt be reproduced? if the ask collected to reproduced would not be able to rerecycled or only so small amount of it couldnt be able to reproduced, the city wont be able to do what it wishes for its polluted air.
correct me if i am wrong, please
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by diebeatsthegmat » Mon May 24, 2010 10:37 am
kevincanspain wrote:You are asked for the assumption underlying the plan. Try to explain why you are confused so we can help!
hi, can you please explain the question/argument posted above? i reread so many times the explanation why the other chose D and i still dont understand and m looking forward to reading your explanation because i still think it should be C here.
i think that way simply. if the city collected refuse. and 80% of it cant be reproduced, the city can still not meet it aim.
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by sk818020 » Mon May 24, 2010 10:53 am
C is incorrect because the passage asks us which is required for the program to achieve its aim. Real quick, the aim of the program is "to reduce the amount of residue ash Shelbyville generats this year to half of last year."

C says that there will be more recyclable material in the garbage this year, than last year. This only tells us that there will be at least one more unit of recyclable material in the garbage than there was last year. Can we definitively say that this will reduce the amount of residue ash to half? No, because what if there was only one more peice of recyclable garbage in the trash this year than there was last year? Will this cause the residue to decrease by 50%, most likely not.

The main issue with C is that is says it will have a larger proportion. A larger proportion of anything means that it could be anything from a tiny increase to a large increase. In this case we need to prove that there will be enough to cut incinerated material to half, which we cannot say for sure based on C alone. Its not enough to garuntee us the conclusion.

Hope this helps.
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by kevincanspain » Mon May 24, 2010 1:55 pm
ssgmatter wrote:Guys can anyone please help me understand the logic on this one...I am really having a tough time with this CR

Last year all refuse collected by Shelbyville city services was incinerated. This
incineration generated a large quantity of residue ash. In order to reduce the amount
of residue ash Shelbyville generates this year to half of last year's total, the city has
revamped its collection program. This year city services will separate for recycling
enough refuse to reduce the number of truckloads of refuse to be incinerated to half
of last year's number.
Which of the following is required for the revamped collection program to achieve its
aim?
A. This year, no materials that city services could separate for recycling will be
incinerated.
B. Separating recyclable materials from materials to be incinerated will cost
Shelbyville less than half what it cost last year to dispose of the residue ash.
C. Refuse collected by city services will contain a larger proportion of recyclable
materials this year than it did last year.
D. The refuse incinerated this year will generate no more residue
ash per truckload incinerated than did the refuse incinerated last year.
E. The total quantity of refuse collected by Shelbyville city services this year will be
no greater than that collected last year.
C need not be true for the aim to be achieved. If the vast majority of last year's trash was recyclable, it is possible for the program to achieve its aim even if this year's refuse contained a smaller proportion of recyclable materials that last year's.

When you see such a plan, do not accept the assumption that half the trash should generate half the ash!

Teenagers usually wreck havoc in our city during the summer months: vandalism, shoplifting, and drag races on city streets have long been common in the 8 weeks between school years. We have organized free summer camps in a remote part of the state, camps for which half of our teenagers have signed up. Thus, we can expect that such crimes will be half as common as they were last summer.

What objections can you raise to this above argument?
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by diebeatsthegmat » Tue May 25, 2010 2:31 am
kevincanspain wrote:
ssgmatter wrote:Guys can anyone please help me understand the logic on this one...I am really having a tough time with this CR

Last year all refuse collected by Shelbyville city services was incinerated. This
incineration generated a large quantity of residue ash. In order to reduce the amount
of residue ash Shelbyville generates this year to half of last year's total, the city has
revamped its collection program. This year city services will separate for recycling
enough refuse to reduce the number of truckloads of refuse to be incinerated to half
of last year's number.
Which of the following is required for the revamped collection program to achieve its
aim?
A. This year, no materials that city services could separate for recycling will be
incinerated.
B. Separating recyclable materials from materials to be incinerated will cost
Shelbyville less than half what it cost last year to dispose of the residue ash.
C. Refuse collected by city services will contain a larger proportion of recyclable
materials this year than it did last year.
D. The refuse incinerated this year will generate no more residue
ash per truckload incinerated than did the refuse incinerated last year.
E. The total quantity of refuse collected by Shelbyville city services this year will be
no greater than that collected last year.
C need not be true for the aim to be achieved. If the vast majority of last year's trash was recyclable, it is possible for the program to achieve its aim even if this year's refuse contained a smaller proportion of recyclable materials that last year's.

When you see such a plan, do not accept the assumption that half the trash should generate half the ash!

Teenagers usually wreck havoc in our city during the summer months: vandalism, shoplifting, and drag races on city streets have long been common in the 8 weeks between school years. We have organized free summer camps in a remote part of the state, camps for which half of our teenagers have signed up. Thus, we can expect that such crimes will be half as common as they were last summer.

What objections can you raise to this above argument?
hi, thank you for your quick reply, i really appreciate that.
all i understand about the argument above is that the city want to reduce the number of damage the teen made for the city by offering a free summer camps for teen in the city.
one question existing in my mind is whether half of the teens who signed up are the ones wrecking havoc in the city??maybe no or maybe in the group of signed up students, there are only a small number of students who usually wreck the city... so the aim for reducing 1/2 the crimes is maybe impossible???
CR is really complicating.... the more i study, the more i am stagnant! maybe its lack of english skill
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by DanaJ » Tue May 25, 2010 3:37 am
Received a PM.

I see some people get confused about the argument and what it's really asking us to do... If you have that sort of issue, then just write down one-two phrases summarizing the thing. Try to do so in your own words, but without altering the meaning of the argument.

So we know that:
- last year, all the refuse from S was incinerated, but this generated a lot of ash
- to reduce this ash to half of last year's quantity, the city will be recycling some of the collected refuse so that the number of truckloads is half of the one from last year

So the goal here is to reduce the quantity of ash by recycling some refuse.

This is indeed a "must be true" type of question. Think of the type this way: if it weren't true, then the argument falls apart.

A is not right because it's not necessary. The argument tells us that some recycling will occur, but this does not mean that every recyclable object will indeed be recycled. All we know is that recycling will help reduce the number of trucks of refuse to be incinerated. We really have no reason to believe that this means everything will be recycled: some stuff might not be recycled (even though it could be), but a good chunk of the refuse will.

B is not the point. As mentioned above, the goal is to reduce the quantity of ash. Cost is not discussed at all.

C might be right, but again, it does not affect the ash output, so to speak. The percentage of recyclable materials in the refuse is not relevant as long as we do not know how much ash is produced. Actually, the argument suggests that this statement is not to be trusted: if we recycle more this year, then the percentage of recyclable materials in the refuse will probably be lower this year than it was in the last year.

D is the correct choice here: the program will ensure that there are fewer "truckloads" of material to be burned. However, if the amount of ash per truckload does not stay the same, then the ash resulted from the incineration will be different from the half we are aiming for. This option provides the necessary link between "truckloads of refuse" and "quantity of ash".

E is again irrelevant because we're interested in the refuse to be incinerated. The total amount of refuse does not matter as long as I get the refuse to be incinerated to half of what it was last year. After all, only incinerated refuse generates ash!
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by kevincanspain » Tue May 25, 2010 4:36 am
diebeatsthegmat wrote:
kevincanspain wrote:
ssgmatter wrote:Guys can anyone please help me understand the logic on this one...I am really having a tough time with this CR

Last year all refuse collected by Shelbyville city services was incinerated. This
incineration generated a large quantity of residue ash. In order to reduce the amount
of residue ash Shelbyville generates this year to half of last year's total, the city has
revamped its collection program. This year city services will separate for recycling
enough refuse to reduce the number of truckloads of refuse to be incinerated to half
of last year's number.
Which of the following is required for the revamped collection program to achieve its
aim?
A. This year, no materials that city services could separate for recycling will be
incinerated.
B. Separating recyclable materials from materials to be incinerated will cost
Shelbyville less than half what it cost last year to dispose of the residue ash.
C. Refuse collected by city services will contain a larger proportion of recyclable
materials this year than it did last year.
D. The refuse incinerated this year will generate no more residue
ash per truckload incinerated than did the refuse incinerated last year.
E. The total quantity of refuse collected by Shelbyville city services this year will be
no greater than that collected last year.
C need not be true for the aim to be achieved. If the vast majority of last year's trash was recyclable, it is possible for the program to achieve its aim even if this year's refuse contained a smaller proportion of recyclable materials that last year's.

When you see such a plan, do not accept the assumption that half the trash should generate half the ash!

Teenagers usually wreck havoc in our city during the summer months: vandalism, shoplifting, and drag races on city streets have long been common in the 8 weeks between school years. We have organized free summer camps in a remote part of the state, camps for which half of our teenagers have signed up. Thus, we can expect that such crimes will be half as common as they were last summer.

What objections can you raise to this above argument?
hi, thank you for your quick reply, i really appreciate that.
all i understand about the argument above is that the city want to reduce the number of damage the teen made for the city by offering a free summer camps for teen in the city.
one question existing in my mind is whether half of the teens who signed up are the ones wrecking havoc in the city??maybe no or maybe in the group of signed up students, there are only a small number of students who usually wreck the city... so the aim for reducing 1/2 the crimes is maybe impossible???
CR is really complicating.... the more i study, the more i am stagnant! maybe its lack of english skill
That's a good objection, and it's analgous to the one we can raise concerning the recycling plan
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by diebeatsthegmat » Tue May 25, 2010 10:33 am
DanaJ wrote:Received a PM.

I see some people get confused about the argument and what it's really asking us to do... If you have that sort of issue, then just write down one-two phrases summarizing the thing. Try to do so in your own words, but without altering the meaning of the argument.

So we know that:
- last year, all the refuse from S was incinerated, but this generated a lot of ash
- to reduce this ash to half of last year's quantity, the city will be recycling some of the collected refuse so that the number of truckloads is half of the one from last year

So the goal here is to reduce the quantity of ash by recycling some refuse.

This is indeed a "must be true" type of question. Think of the type this way: if it weren't true, then the argument falls apart.

A is not right because it's not necessary. The argument tells us that some recycling will occur, but this does not mean that every recyclable object will indeed be recycled. All we know is that recycling will help reduce the number of trucks of refuse to be incinerated. We really have no reason to believe that this means everything will be recycled: some stuff might not be recycled (even though it could be), but a good chunk of the refuse will.

B is not the point. As mentioned above, the goal is to reduce the quantity of ash. Cost is not discussed at all.

C might be right, but again, it does not affect the ash output, so to speak. The percentage of recyclable materials in the refuse is not relevant as long as we do not know how much ash is produced. Actually, the argument suggests that this statement is not to be trusted: if we recycle more this year, then the percentage of recyclable materials in the refuse will probably be lower this year than it was in the last year.

D is the correct choice here: the program will ensure that there are fewer "truckloads" of material to be burned. However, if the amount of ash per truckload does not stay the same, then the ash resulted from the incineration will be different from the half we are aiming for. This option provides the necessary link between "truckloads of refuse" and "quantity of ash".

E is again irrelevant because we're interested in the refuse to be incinerated. The total amount of refuse does not matter as long as I get the refuse to be incinerated to half of what it was last year. After all, only incinerated refuse generates ash!
thanks alot. your explaination and kevincanspain's explaination really help alot.
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