Critical Reasoning

The OA is C

I am stuck between C and E.

mehravikas wrote:I am stuck between C and E.

E is irrelevant because of this sentence in the passage:

Elementary school nurses in Renston report that the proportion of schoolchildren sent to them for treatment of allergic reactions to those chemicals has increased significantly over the past ten years.

Now, if that sentence had said "number" rather than "proportion", then choice E would also be a necessary assumption.

yeah I get it now. CRs....damn...!!

Testluv wrote:

mehravikas wrote:I am stuck between C and E.

E is irrelevant because of this sentence in the passage:

Elementary school nurses in Renston report that the proportion of schoolchildren sent to them for treatment of allergic reactions to those chemicals has increased significantly over the past ten years.

Now, if that sentence had said "number" rather than "proportion", then choice E would also be a necessary assumption.

yeah I get it now. CRs....damn...!!

Actually, I think you mean CRs....yaaaay ...!!

The day I feel I have even half of the skills you have for CRs I'll say CRs..yaaaay

Testluv wrote:

yeah I get it now. CRs....damn...!!

Actually, I think you mean CRs....yaaaay ...!!

Guys, please explain options C and E in more details......I am really having tough time to understand the options in the context of the argument.....

Also as testluv pointed out that in E proportion is a problem....please also throw some light on this aspect...

Thanks in advance!

ildude02 wrote:Can you explain how E cannot be an assumption since if we negate E, the argument seems to fall apart as well. Appreciate your response.

IMO C
E is wrong because it is saying about proportion, not about absolute number.
There might be possibility that the number of children in elementary school has reduced but proportion has increased.

Received a PM.

You need to look at the structure of the argument first. This is one of the most common question types in that it uses percentages or proportions (remember: a percentage is simply a proportion with the denominator 100) to mess with your head, so to speak.

Let's look at the structure of the argument first:
- certain chemicals used in schools cause allergies
- nurses report that a greater PROPORTION of schoolchildren are being sent to them because of allergies
- either the schoolchildren are more exposed to the stuff or they are more sensitive

C is clearly the winner. It exposes the necessary connection between the number of children being exposed to chemicals or more sensitive to them and children being sent to the nurses. If we are sure that teachers are no more likely to send children to the nurse, then the argument is valid. If, on the other hand, teachers are more likely to send a kid to the nurse because of a rash or some other allergic reaction, then it's only natural for the nurses to "see" more.

E is out because the argument discusses strictly schoolchildren:

Exposure to certain chemicals commonly used in elementary schools as cleaners or pesticides causes allergic reactions in some children. Elementary school nurses in Renston report that the proportion of schoolchildren sent to them for treatment of allergic reactions to those chemicals has increased significantly over the past ten years. Therefore, either Renston's schoolchildren have been exposed to greater quantities of the chemicals, or they are more sensitive to them than schoolchildren were ten years ago.

The general population is not relevant. Also, because we're discussing proportions, the total numbers are again not important.

Hi Dana

Not still clear with C here....i dont understand as to how by negating option C is making the argument invalid...

also in case of option E here it only talks about the elementary schools children...do you really think it is talking about other children?

Please advise

OK I'll try to give you an example. However, just a bit of advice: this type of question is VERY common and among the easier of CR questions. If you do not understand it properly and pretty fast, you might get into trouble later on. It's doable! You can do it!
You have the following case: the school had 500 children ten years ago and has 500 children now as well. At present, 10 kids come to the nurse with allergies. In 2000, only 5 kids came to the nurse.

The proportion is obviously bigger now than 10 years ago, since 10/500 > 5/500.

So let's take C and negate it. We have:

Children who have allergic reactions to the chemicals are more likely to be sent to a school nurse now than they were ten years ago

This tells us that the kids' supervisors are more cautious today than they were ten years ago. This could mean that ten years ago 11 kids were allergic to the substances, but fewer were sent to the nurse because teachers were not paying attention. If this is the case, then the argument falls apart because there is an ALTERNATIVE EXPLANATION to the increase in proportion: teachers' care.

About E: I never said E is about other children. The argument concerns strictly schoolchildren and the proportion of allergic kids among schoolchildren. Proportions involving something other than schoolchildren are irrelevant to the argument.

E is playing on your attention. The argument strictly says "proportion of schoolchildren sent to the nurse". E suggests that the population might have changed, so the total number of kids sent to the nurse is different. However, the TOTAL NUMBER is not important, it's just the proportion.

DanaJ wrote:OK I'll try to give you an example. However, just a bit of advice: this type of question is VERY common and among the easier of CR questions. If you do not understand it properly and pretty fast, you might get into trouble later on. It's doable! You can do it!
You have the following case: the school had 500 children ten years ago and has 500 children now as well. At present, 10 kids come to the nurse with allergies. In 2000, only 5 kids came to the nurse.

The proportion is obviously bigger now than 10 years ago, since 10/500 > 5/500.

So let's take C and negate it. We have:

Children who have allergic reactions to the chemicals are more likely to be sent to a school nurse now than they were ten years ago

This tells us that the kids' supervisors are more cautious today than they were ten years ago. This could mean that ten years ago 11 kids were allergic to the substances, but fewer were sent to the nurse because teachers were not paying attention. If this is the case, then the argument falls apart because there is an ALTERNATIVE EXPLANATION to the increase in proportion: teachers' care.

About E: I never said E is about other children. The argument concerns strictly schoolchildren and the proportion of allergic kids among schoolchildren. Proportions involving something other than schoolchildren are irrelevant to the argument.

E is playing on your attention. The argument strictly says "proportion of schoolchildren sent to the nurse". E suggests that the population might have changed, so the total number of kids sent to the nurse is different. However, the TOTAL NUMBER is not important, it's just the proportion.

Make sense now!

Thankyou Dana.

I will go with 'A'. Pls post OA and also please quote the source.

paddle_sweep wrote:I will go with 'A'. Pls post OA and also please quote the source.

Hi,

the correct answer is most certainly choice C as DanaJ thoroughly discussed.

But I can see why choice A is tempting you! However, the passage discusses the "elementary school nurses" as a group. It doesn't say that each individual nurse is now receiving more of such students. So, the reasoning of the argument does not depend on the idea that there aren't more nurses than there used to be.

Testluv wrote:

paddle_sweep wrote:I will go with 'A'. Pls post OA and also please quote the source.

Hi,

the correct answer is most certainly choice C as DanaJ thoroughly discussed.

But I can see why choice A is tempting you! However, the passage discusses the "elementary school nurses" as a group. It doesn't say that each individual nurse is now receiving more of such students. So, the reasoning of the argument does not depend on the idea that there aren't more nurses than there used to be.

Excellent.Thanks.