PR Question

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by jayhawk2001 » Wed Jun 06, 2007 12:03 pm
a = (7,3)
b = (x, 8)

(x-7)^2 + (8-3)^2 = 169

(x-7)^2 = 144 = 12^2
x = 19

Can't see how x-coordinate is 12

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by f2001290 » Wed Jun 06, 2007 12:12 pm
This is a question from PR Test. Even i went with 19. But the OA has stumped me .

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by jayhawk2001 » Wed Jun 06, 2007 5:21 pm
f2001290 wrote:This is a question from PR Test. Even i went with 19. But the OA has stumped me .
Hmm, if B=12,8 and A=7,3

Distance between A and B = sqrt ( 25 + 25) = sqrt(50). But we are given
that distance AB = 13 units.

So, unless I'm reading the question incorrectly, I don't see how it can be 12.

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by Sadowski » Thu Jun 07, 2007 6:00 am
Consider the distance between A and B the hypotenuse of your triangle = 13.

One of the adjacent sides has to equal 5 because we know the y-coordinates of both points (8-3).

This problem doesn't require any calculations because it's a special triangle - 5-x-13.

We have a 5-12-13 triangle.

x=12

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by Sadowski » Thu Jun 07, 2007 6:09 am
Oops! :oops: Answered before I fully read the problem! How could 12 actually be right? It has to be 19.

You know, Eric mentioned that the grading was not correct on one of his PR tests. He said that the software counted some number of correct answers as incorrect.

Sounds like that might be the case here...

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Eric's experience

by Sadowski » Thu Jun 07, 2007 6:12 am
Quoted from Eric, Sunday, May 08, 2005 - PR CAT2 Analysis

"This evening I went through the practice GMAT that I took last Friday to gather data for analysis. I discovered something that both shocked and relieved me:

PRINCETON REVIEW SOFTWARE SUCKS!

After double- and triple-checking the answer key, I found that the PR software made an error in scoring my test. On the quantitative section, PR scored question #2 as wrong when I had in fact scored that question right. Thus, my final result of 690 for this particular practice test doesn't mean shit. Getting a question marked wrong so early in the section brought my score down dramatically (the way the GMAT is designed, it's critical to start off strong to achieve a high score). My score is probably skewed down.
"