IR Graphics Interpretation Question

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IR Graphics Interpretation Question

by kaudes11114 » Thu Jan 09, 2014 8:42 am
Hi

Request your help to solve below problem

https://www.veritasprep.com/sample-problems/?question=14

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by [email protected] » Thu Jan 09, 2014 11:30 am
kaudes11114 wrote:Hi

Request your help to solve below problem

https://www.veritasprep.com/sample-problems/?question=14
Dear kaudes11114,
I'm happy to respond. :-)

This Veritas question is a good question. It's a bubble graph. See this blog for a detailed explanation of this graph type:
https://magoosh.com/gmat/2012/gmat-integ ... le-charts/

In this question
F determines the horizontal position of the center of each circle.
S determines the vertical position of the center of each circle.
L determines the area of the circle

All the questions contain a fundamental ambiguity. If the relationship of L and S is reversed, the question is: which one remains fixed in its relationship with F? Technically, the relationship of L and S would be reversed if L & F stayed the same, and only S changed, or if S & F stayed the same, and only L changed. That, I feel, is a problem with the question: a good GMAT question doesn't contain any ambiguity. I assume they mean that S & F stay the same, and only L changes, but because that is not specified, I am taking a guess on their intention. I will make that assumption and go through the questions with that assumption.

1) If the relationship between L and S were inversed, then the greatest effect on the graph would be to the ________ of the circles.
Well, if the relationship of S & F remains unchanged, which I believe is what they are implying, then the centers of the circles would remain in the same place. If new trend is that the more sporty perception of the car makes folks less likely to buy, then the bigger circles would be on the lower left, and the smaller ones, on the upper right. Thus, the effect would be to the size of the circles.

If the relationship between L and S were inversed, then the largest circle would be ________.
Again, the largest circle would be lower left, Circle A.

3) If the relationship between L and S were inversed, then were would be a ________ correlation between F and L.
Right now, in the graph as it stands, there's a positive correction between F & L: as F increases (to the right), L increases (the circles get bigger). If L reversed, and F & S remained the same, the bigger circles would be on the lower left, and the smaller ones on the upper right. As F increased, to the right, the circles would get smaller. When F goes up, L goes down. That's a negative correlation.

4) If the relationship between L and S were inversed, then were would be a ________ correlation between S and L.
Right now, on the current graph, as S increases (we move up), L increases (the circles get bigger): a positive correlation. If we reverse either of the variables in a positive correlation, we get a negative correlation.

5) If the relationship between L and S were inversed, then were would be a ________ correlation between F and S.
Right now, as we move left, the centers of the circles move up. In other words, as F increases, S increases. That's a positive correlation. If L reversed, and F & S remained the same, then F & S would keep the same correlation. The size of the circles would change, but the centers of the circles would be in the same places. Thus, F & S wold keep their positive correlation.

These are the five answers that Veritas wanted, so I seem to have made the correct assumption about their intention. Nevertheless, this is absolutely something you will not have to do on the real GMAT. The real GMAT will not give you something open to ambiguous interpretations and make you guess.

Does all this make sense?
Mike :-)
Magoosh GMAT Instructor
https://gmat.magoosh.com/

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by kaudes11114 » Thu Jan 09, 2014 4:54 pm
Yes that make sense. I actually tried to solve it through MS Excel in which i was changing the relation between F & S and hence was getting totally different answers.
Thanks for your reply.