Raome
Hello, I am having difficulty understanding the target values here. The current explanations don't seem reliable. Can you please post the official answer for this?
JoeAa
May I know how to cut down the time spent on Q1 for testng.
I wanted to respond to both of these questions!
JoeAa do you mean statement 1? If so, I can see why you'd want to cut down the time for testing, because at first glance this seems like a lot. But here's how I handled it, so maybe this will help! Also, NOTE I take some issue with the wording of statement 3 - the language isn't tight enough for GMAT standards and so would likely be rewritten (see below).
Stm1: No country's emissions were 50 percent or more below that country's 2012 target during any year measured.
What the table shows - 2012 target against 2008, so if we can show that any of the countries had a score in that column of -50 or more negative, then this choice would be false. If we sort, we get that the lowest (or highest negative) values are for Estonia and Latvia, and both are VERY close to 50%, but not quite there (-49.25% and -48.93% respectively). So we don't have any country that was 50 percent or more below the 2012 target in 2008. But what about in any other year? That might require some computation. One option is to set up an equation to calculate, from the 2008 values, what the 2012 target actually was, but before we do that, let's
eyeball a minute. For Estonia for example, if the 2008 value of 20.3 was very close to being 50%
under then something
lower than 20.3 in another year might be enough to be over that 50% threshold. The fact that 2006 was 19.2 is a good candidate! You could do the same looking at Latvia - since 2008 was 11.9 but 2004 was 10.7, maybe 10.7 is a good candidate! You could even scan the next few countries (Lithuania, Romania, or even Bulgaria), but those 2008-2012 percentages are getting further and further from 50%, so a year from 2004-2007 would have to have a much lower number than 2008 to make up the difference.
Once I decided to try Estonia, I did do the computation to see what the 2012 target would have been using the equation below (where T is the 2012 target):
T - 0.4925*T = 20.3
0.5075*T = 20.3
T = 40
So if the target was 40, and we're looking for something more than 50% under that, we need something under 20, and 2006 IS under 20. So this statement is
No!
(just a note, other countries also had years that were more than 50% below the target goal, but we only need to show this for one of them for it to be false).
Stm 2: The same country had the median carbon dioxide emissions in all 5 years measured.The median of 25 countries will be the 13th country counted from either the highest or lowest end. So you need to sort each column to make sure that the same country is in that 13th spot. I found the 13th row and then held my finger there while I sorted by all 5 yearly columns. Beware, do NOT sort by the emissions relative to 2012 because that is not part of the question. But if you sort on 2004 - 2008, Portugal is in that 13th spot every time! The answer is
Yes.Problematic Stm 3: The country with the median percentage of carbon dioxide emissions in 2008 relative to its 2012 Kyoto target was below its target in all 5 years measured.The issue I have here is the ambiguity around "its target." The "correct" answer clearly assumes that we're comparing all 5 years against the country's 2012 target, but the language as is doesn't clarify that. In fact, if anything, I would assume that this language means the country's targets for 2004, 2005, 2006, 2007, and 2008 - targets that we have zero information about. In that reading, the correct answer here would be No. But if we were to rewrite the problem to what I think this writer wants we'd have the following:
CORRECTED Stm 3: The country with the median percentage of carbon dioxide emissions in 2008 relative to its 2012 Kyoto target was below THAT target in all 5 years measured.
This statement IS about the median of that last column. So finger back on the portugal row if sorted by any of the 2004-2008 and then sort by the Kyoto comparison column. The country in the 13th slot now is France. We will use the same equation as in Stm1 to find the 2012 target based on the 2008 value we know.
T - 0.0656T = 527
0.9344*T = 527
T = 563.998
Since all of the years 2004-2008 are below this amount, this statement (as written now) is Yes. Hope this helps!:)Whit