Picking numbers...

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Picking numbers...

by Oracio » Tue Jun 19, 2007 7:58 pm
This problem is from The Official GMAT Quantitative Review 2005 (a GMAC publication; page 76, problem 111)

Any idea how to solve this problem using the Kaplan method of picking numbers?? Is it possible??


Problem: If k does not equal zero and k - [(3 – 2k^2)/2] = x/K, then x =

A. -3 – k^2
B. k^2 – 3
C. 3k^2 – 3
D. k – 2k^2
E. k – 3 + 2k^2

The answer is C.
Source: — Problem Solving |

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by Neo2000 » Wed Jun 20, 2007 8:04 am
Just put k = 2

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by Oracio » Wed Jun 20, 2007 4:29 pm
funny, as I had been working with that vary value. When K = 2, x = 7 and, using those values, I could not get a single answer choice to give me 7 when k = 2. Did using k =2 allow you to answer the question correctly?

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by Oracio » Wed Jun 20, 2007 4:57 pm
crap! as i suspected, my mistake was due to a silly arithmetic mistake. You were right, K = 2 does work. Thanks!


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