How many people are standing in line

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How many people are standing in line

by BTGmoderatorDC » Fri Dec 01, 2017 5:55 am
How many people are standing in line?

(1) Three people are standing in front of Alan and three people are standing behind David.

(2) Two people are standing between Alan and David.

Can some experts figure it out?

OA E

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alan and david

by GMATGuruNY » Fri Dec 01, 2017 6:08 am
lheiannie07 wrote:How many people are standing in line?

(1) Three people are standing in front of Alan and three people are standing behind David.

(2) Two people are standing between Alan and David.
Statements combined:
Case 1: Back<-----A, X, X, D----->Front
Here, there are two people between Alan and David (X, X), 3 people in front of Alan (X, X, D), and 3 people behind David (A, X, X).
Total number of people = 4.

Case 2: Back<-----X, X, X, D, X, X, A, X, X, X----->Front
Here, there are two people between Alan and David (X, X), 3 people in front of Alan (X, X, X), and 3 people behind David (X, X, X).
Total number of people = 10.

Since the total number of people can be different values, the two statements combined are INSUFFICIENT.

The correct answer is E.
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