BTGmoderatorLU wrote:Source: Official Guide

If a building has 6,000 square meters of floor space, how many offices are in the building?

1) Exactly \(1/4\) of the floor space is not used for offices.
2) There are exactly 20 executive offices and each of these occupies 3 times as much floor space as the average for all of the remaining offices.

The OA is E

Let's take each statement one by one.

1) Exactly \(1/4\) of the floor space is not used for offices.

=> 3/4 of the floor space is used for offices = 3/4 of 6,000 = 4,500 sq feet

Can't get the number of offices in the building. Insufficient.

2) There are exactly 20 executive offices and each of these occupies 3 times as much floor space as the average for all of the remaining offices.

Say there are x remaining offices and each occupies y sq feet area; thus, each of 20 executive offices occupies 3y sq feet area.

=> xy + 30y = Area occupied

Can't get the number of offices in the building. Insufficient.

(1) and (2) together

From both statements, xy + 30y = 4,500

Can't solve this. Insufficient.

The correct answer: E

Hope this helps!

-Jay
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