OG 2015

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OG 2015

by tapanmittal » Mon Aug 17, 2015 10:25 am
114. A department manager distributed a number of pens,
pencils, and pads among the staff in the department,
with each staff member receiving x pens, y pencils,
and z pads. How many staff members were in the
department?
(1) The numbers of pens, pencils, and pads that
each staff member received were in the ratio
2:3:4, respectively.
(2) The manager distributed a total of 18 pens,
27 pencils, and 36 pads.

OA-E
Source: — Data Sufficiency |

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by GMATGuruNY » Mon Aug 17, 2015 11:25 am
A department manager distributed a number of pens, pencils, and pads among the staff in the department, with each staff member receiving x pens, y pencils, and z pads. How many staff members were in the department?

(1) The numbers of pens, pencils, and pads that each staff member received were in the ratio 2:3:4, respectively.

(2) The manager distributed a total of 18 pens, 27 pencils, and 36 pads.
Statement 1: The numbers of pens, pencils, and pads that each staff member received were in the ratio 2:3:4, respectively.
Since 2+3+4 = 9, the total number of pens + pencils + pads must be a multiple of 9.
No way to determine the exact number of staff members.
Insufficient.

Statement 2: The manager distributed a total of 18 pens, 27 pencils, and 36 pads.
The given values are divisible both by 3 and by 9. Thus:
There could be 3 staff members, each receiving 6 pens, 9 pencils, and 12 pads.
There could be 9 staff members, each receiving 2 pens, 3 pencils, and 4 pads.
Since the number of staff members could be 3 or 9, insufficient.

Statements 1 and 2 combined:
In statement 2, pens:pencils:pads = 18:27:36 = 2:3:4, the same ratio given in statement 1. Thus, statement 1 offers no information beyond what is given in statement 2:
There could be 3 staff members, each receiving 6 pens, 9 pencils, and 12 pads.
There could be 9 staff members, each receiving 2 pens, 3 pencils, and 4 pads.
Since the number of staff members could be 3 or 9, insufficient.

The correct answer is E.
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by Brent@GMATPrepNow » Mon Aug 17, 2015 11:43 am
Mitch's solution is great.
I just wanted to mention that this question hinges largely on the fact that the number of pens, pencils, and pads that each staff member receives MUST BE AN INTEGER.

So, for example, if statement 1 were different and statement 2 read "The manager distributed a total of 11 pens, 2 pencils, and 13 pads," then we could be certain that there must be only 1 staff member, since there's no other way for each staff member to receive the same number of items. So, in this case, statement 2 would be sufficient on its own.

Conversely, if statement 1 were different and statement 2 read "The manager distributed a total of 10 pens, 12 pencils, and 14 pads," then we could NOT be certain of the number of staff members. In this instance, there could be 1 staff member or 2 staff members, so statement 2 would be insufficient on its own.

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by Brent@GMATPrepNow » Mon Aug 17, 2015 11:46 am
Here's a related question for extra practice: https://www.beatthegmat.com/gmat-prep-qu ... 84492.html

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