Obesity

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Obesity

by vikram_k51 » Sun Aug 23, 2009 4:50 am
The number of North American children who are obese-that is, who have more body fat than do 85 percent of North American children their age-is steadily increasing, according to four major studies conducted over the past 15 years.
If the finding reported above is correct, it can be properly concluded that
(A) when four major studies all produce similar results, those studies must be accurate
(B) North American children have been progressively less physically active over the past 15 years
(C) the number of North American children who are not obese increased over the past 15 years
(D) over the past 15 years, the number of North American children who are underweight has declined
(E) the incidence of obesity in North American children tends to increase as the children grow older
OA C
Source: — Critical Reasoning |

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by mehravikas » Wed Sep 09, 2009 10:53 pm
I really doubt that the OA is C. What's the source?

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by MaxPower » Thu Sep 10, 2009 5:59 am
Why? It kinda makes sense (except for the dodgy definition of obesity, even if it is the right one).

The number of North American children who have more body fat than 85% of children their age is always 15% of the children that age.

So this number, which is always 15% of children, increased. This can only mean that the 100% of children increased, meaning also the remaining 85% (children who are not obese) increased.

vikram - can you tell us where you got this question?

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by heshamelaziry » Thu Sep 10, 2009 8:16 am
MaxPower wrote:Why? It kinda makes sense (except for the dodgy definition of obesity, even if it is the right one).

The number of North American children who have more body fat than 85% of children their age is always 15% of the children that age.

So this number, which is always 15% of children, increased. This can only mean that the 100% of children increased, meaning also the remaining 85% (children who are not obese) increased.

vikram - can you tell us where you got this question?
The stimuli does not indicate that the number of obese children is always 15% of all children. It says that this percentage has been increasing the past 15 years !!!!

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by bharathh » Thu Sep 10, 2009 8:21 am
It says the number is increasing. Not the %. The % has to be the same for the definition of obesity to stick.

I agree with max

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by mehravikas » Thu Sep 10, 2009 11:27 am
yes it says..but how can you say that number of children who are not obese has also increased?
bharathh wrote:It says the number is increasing. Not the %. The % has to be the same for the definition of obesity to stick.

I agree with max

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by vivek.kapoor83 » Fri Sep 11, 2009 10:21 am
im not conviunced with OA..wht is d source of ques....

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by akhpad » Wed Jul 21, 2010 9:47 pm
Source: Power Score CR/LR Bible

Actual source: Official LSAT past question

I am unable to understand that how figure 15% and 85% is fixed. What grammar am I missing?

Number of obese children = 15%
Number of non-obese children = 85%
These information is fixed over time. This is the only point that I am missing.

Can someone explain it?

OA: C

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by bdiwakarteja » Wed Jul 21, 2010 10:12 pm
akhp77 wrote:Source: Power Score CR/LR Bible

Actual source: Official LSAT past question

I am unable to understand that how figure 15% and 85% is fixed. What grammar am I missing?

Number of obese children = 15%
Number of non-obese children = 85%
These information is fixed over time. This is the only point that I am missing.

Can someone explain it?

OA: C
Let me try to explain you how the percentages have come in. From the definition of the obesity in the passage, it says that a child can be said as obese if he outweighs/overweighs 85% of the all other north american children of his age.
This directs us that the number of children that can be obese and will be obese at anypoint in time is only 15% of the total amount. However, when the stimulus says that this 15% of the children is increasing in number, it means that the total number of children are increasing.This also means for sure that the number of children who are not obese are increasing for the past 15 years.

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by lunarpower » Thu Oct 07, 2010 4:32 am
received a PM.

i really can't improve on this:
MaxPower wrote:Why? It kinda makes sense (except for the dodgy definition of obesity, even if it is the right one).

The number of North American children who have more body fat than 85% of children their age is always 15% of the children that age.

So this number, which is always 15% of children, increased. This can only mean that the 100% of children increased, meaning also the remaining 85% (children who are not obese) increased.

vikram - can you tell us where you got this question?
perfect explanation.

since i'm sure that everybody on this board understands percentiles, think about it this way: the passage is basically defining obesity as being in the 85th or higher percentile of body fat.
given the way percentiles work, the number of children who satisfy this definition will always be exactly 15% of the total number of children. therefore, the only way for this number to increase is for the entire population of children to increase.

i agree that this question is not very typical of what you would see on the gmat. ironically, if you ever saw a question similar to this one on the gmat, you would probably encounter it in the quant section, not in CR.
Ron has been teaching various standardized tests for 20 years.

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