Waste management companies, which collect waste for disposal in landfi

OFFICIAL EXPLANATION

The structure of the argument, in simplified form, is as follows: Premise: Disposable plastics make up an ever-increasing percentage of the waste they handle. Conclusion: Attempts to decrease the amount of plastic that people throw away in the garbage are failing. Based on our discussion of numbers and percentages, it should be clear that the conclusion is flawed: a numbers conclusion (“amount”) cannot be drawn solely from percentage information because the overall total could change dramatically. As you attack the answer choices, look for an answer that addresses this error.

Answer choice (A): The argument is about how people act when throwing away garbage, an issue that occurs before the waste management companies receive the trash. On the other hand, this answer discusses how the waste management companies dispose of plastics, an issue that occurs after they have received the waste. Because the two issues occur at different times in the cycle, this answer does not attack the argument and is incorrect.

Answer choice (B): Like answer choice (A), this answer raises an issue that occurs after the waste management companies have received the waste.

Answer choice (C): This answer addresses how people act prior to throwing away garbage, but it does not suggest that the amount of plastic that people throw away is not decreasing. The author would probably counter this statement by saying that regardless of the fact that people are more likely to save plastic containers, that tendency is only relative to glass and metal containers, and people are still throwing away plastics in an ever-increasing percentage (and thus amount).

Answer choice (D): This is the correct answer. The answer indicates that the waste management companies no longer receive as much paper, glass, and metal as they used to. Since this clearly affects the amount of trash that they process, this would also affect the percentages of each type of waste. If the amount of paper, glass, and metal drops by a large amount, the percentage of plastic in the waste would rise even if the actual amount of plastic waste was reduced. The following example shows how this is possible:

Previously Now
Total garbage 100 20 (in units)
Plastic garbage 20 (20%) 10 (50%) (in units)
Other garbage 80 (80%) 10 (50%) (in units)

In the example, plastic garbage has risen from 20% to 50%, but the actual amount of plastic waste has decreased from 20 units to 10 units. Consequently, because this answer raises a scenario that could disprove the argument, it is the correct answer.

Answer choice (E): The amount of plastic being manufactured is not the issue in the stimulus; how much plastic is thrown away is the issue. In all respects this is a classic numbers and percentages Weaken problem. Accordingly, we can use this discussion to highlight a general rule for handling Weaken and Strengthen questions paired with numbers and percentages stimuli: To weaken or strengthen an argument containing numbers and percentages, look carefully for information about the total amount(s)— does the argument make an assumption based on one of the misconceptions discussed earlier?

D is the answer:
catch in the argument is "PERCENTAGE"
main point :plastic waste is increasing
two type of waste A and B -
A = other waste -100 (before any plastic waste program)
B = plastic-100(before any plastic waste program

Now recycling of other waste is also increasing .
Currently
A = 50
B = 60
although plastic waste dec. but other waste decreased more .So percentage is high for plastic.

IMO, the conclusion is that people are not attempting to reduce plastic waste thrown in landfill.
Choice C indicates that people want to reuse plastic container instead of metal one.
Hence C is correct.


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(A) Because plastics create harmful pollutants when burned, an increasing percentage of the plastics handled by waste management
companies are being disposed of in landfills. - strengthens.

(B) Although many plastics are recyclable, most of the plastics disposed of by waste management companies are not. - irrelevant.

(C) People are more likely to save and reuse plastic containers than containers made of heavier materials like glass or metal. - are more likely...ummmm...we need a strong argument to weaken the conclusion. Thus doesn't weaken it at all.

(D) An increasing proportion of the paper, glass, and metal cans that waste management companies used to handle is now being
recycled. - this indicates that due to the decrease in the total waste due to others being sent for recycling, the proportion of plastic waste might have increased. However, this doesn't mean that the attempts to reduce the amount of plastic waste has failed. Looks decent to me. Keep.

(E) While the percentage of products ((using plastic packaging is increasing)), the total amount of plastic being manufactured has remained unchanged.
- ok. So this also kinda strengthens the argument.

Hence, D is best.

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Premise:
Disposable plastics are making up an ever-increasing percentage of the waste.
Conclusion:
Attempts to decrease the amount of plastic that people throw away in the garbage are failing

We need to weaken the conclusion. So we need to provide an explanation for how the amount of plastic people throw away may actually be decreasing. How can disposable plastic make up an ever increasing percentage of the waste then?

Say if waste were 100 tonnes. Disposable plastic - 50 tonnes (50%), Other - 50 tonnes
Now if waste is 60 tonnes, disposable plastic - 40 tonnes (66.6%), other - 20 tonnes

If "other" is decreasing faster than plastic, the percentage of plastic will increase even if the actual amount is decreasing.

(A) Because plastics create harmful pollutants when burned, an increasing percentage of the plastics handled by waste management
companies are being disposed of in landfills.

We are discussing the total amount of plastic that goes in landfills and is incinerated. So the split between them is irrelevant.

(B) Although many plastics are recyclable, most of the plastics disposed of by waste management companies are not.

Whether the plastic is recyclable or not is irrelevant. We are only concerned about the quantum of disposable plastic being handled by these companies.

(C) People are more likely to save and reuse plastic containers than containers made of heavier materials like glass or metal.

If people are more likely to reuse plastic, and not other materials, disposable plastic should not be making up an ever increasing percentage of waste. But our premise has to be true.

(D) An increasing proportion of the paper, glass, and metal cans that waste management companies used to handle is now being
recycled.

This says that more and more paper, glass and metal is being recycled. So less is going to the waste management companies. So it says that "other" may be decreasing quite a lot. So this could certainly imply that the amount of plastic that people throw away is decreasing but since other is decreasing more, the plastic makes up a higher percentage of the waste. This information certainly weakens our claim that people are not reducing the amount of plastic they are throwing. It is certainly possible that they are. Hence it weakens our conclusion.
We don't have to prove beyond doubt that the conclusion is wrong. We just have to sow a doubt.

(E) While the percentage of products using plastic packaging is increasing, the total amount of plastic being manufactured has remained unchanged.

The total amount of plastic being manufactured is irrelevant. We are only talking about disposable plastic that reaches waste management companies.

Answer (D)

A question like this you ignore a small clue like the word "percentage" and you end up getting the question wrong. I think the key to getting the CR question is give attention to detail.

Waste management companies, which collect waste for disposal in landfills and incineration plants, report that disposable plastics make up an ever-increasing percentage of the waste they handle. It is clear that attempts to decrease the amount of plastic that people throw away in the garbage are failing.

Which one of the following, if true, most seriously weakens the argument?

(A) Because plastics create harmful pollutants when burned, an increasing percentage of the plastics handled by waste management companies are being disposed of in landfills. - WRONG. What about people? Irrelevant thus.

(B) Although many plastics are recyclable, most of the plastics disposed of by waste management companies are not. - WRONG. So what!!. Nothing more is said. Irrelevant.

(C) People are more likely to save and reuse plastic containers than containers made of heavier materials like glass or metal. - WRONG. Okay, good enough to make one pause and notice. But it does not let's us identify whether there is an increase or decrease in plastic being thrown away. A comparison is unhelpful.

(D) An increasing proportion of the paper, glass, and metal cans that waste management companies used to handle is now being recycled. - CORRECT. POE helps. Half the information was shared in the passage and other half here in this option. True that attempts as far as plastic is concerned might be failing but it might be equally possible that plastic amount thrown is constant and other material waste is, at the same time, decreasing(as it is being recycled).

(E) While the percentage of products using plastic packaging is increasing, the total amount of plastic being manufactured has remained unchanged. - WRONG. Neutral. Plastic packaging usage is irrelevant, though not fully but how plastic is being wasted is not at all inferable from this. All we can say that since manufacturing is constant and since packaging usage is increasing, it suggests that plastic is being reused. So, it takes further assumptions to be made for this to happen. We don't have a sure situation about how plastic is being thrown away in the garbage.

Answer D.