One approach is to use the INPUT-OUTPUT approach (described in our free video - http://www.gmatprepnow.com/module/gmat- ... /video/933)

We have two fractions (1/10 and 1/3), so let's let e = the least common denominator of these two fraction.
We'll let e = 30

If there are 30 employees, then the number of vice-presidents = (1/10)(30) = 3

one-third of the remaining employees are assistant vice-presidents
There are 27 employees remaining.
1/3 of 27 = 9, so there are 9 assistant vice-presidents

So, the total number of vice-presidents AND assistant vice-presidents = 3 + 9 = 12
So, the number of employees who are NEITHER vice-presidents nor assistant vice-presidents = 30 - 12 = 18

So, when the INPUT e = 30, the OUTPUT is 18 people who are NEITHER vice-presidents nor assistant vice-president

Now check the answer choices to see which one yields an OUTPUT of 18, when we INPUT e = 30

A. e/30 = 30/30 = 1 - NO - ELIMINATE
B. 2e/5 = 2(30)/5 = 12 - NO - ELIMINATE
C. 13e/30 = 13(30)/30 = 13 - NO - ELIMINATE
D. 17e/30 = 17(30)/30 = 17 - NO - ELIMINATE
E. 3e/5 = 3(30)/5 = 18 - YES - KEEP

Answer: E

Cheers,
Brent
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Here some additional videos that will help with this question:
- Tips for the Algebraic Approach - http://www.gmatprepnow.com/module/gmat- ... /video/934
- Tips for the Input-Output Approach - http://www.gmatprepnow.com/module/gmat- ... /video/935

Cheers,
Brent
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Hi All,

TESTing VALUES (the approach that Brent used) works perfectly on these types of questions. Rather than rehash the work that he did, I want to point out one of the ways to choose the 'perfect' starting value in these types of situations. Looking at the 5 answer choices, the common denominator is 30, so we should use 30 as the value for the total number of employees. From there, the remaining steps are essentially just basic arithmetic. A bit of note-taking and math will get you to the correct answer.

GMAT assassins aren't born, they're made,
Rich
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Yeah, dave13

Your solution is correct. However we are told that there are e employees in attendance, so it's better to have the number of employees as "e"
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