Hi All,
We're told that a building has 6,000 square meters of floor space. We're asked for the number offices in the building. Since we're given the total floor space, to answer this question, we'll need to have some really specific data about the respective size(s) of the offices. This question can be solved with a bit of logic and TESTing VALUES.
(1) Exactly 1/4 of the floor space is NOT used for offices.
With the information in Fact 1, we know that 3/4 of the office space (re: 3/4 x 6000 = 4500 square meters) is used for office space, but we don't know the size(s) of the offices, so we don't know how many there are.
Fact 1 is 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.
Fact two gives us a ratio between 1 executive office and the AVERAGE of the remaining offices, but we don't know how many "other" offices there actually are - and no actual areas to work with.
Fact 2 is INSUFFICIENT
Combined, we know...
-Exactly 1/4 of the floor space is not used for offices (re: 4500 square meters of space).
-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.
Combined, we still don't have much information to work with.
IF....
-Each executive office is 150 square meters, then the average of the remaining office is 50 square meters - and we have 20 executive offices and 30 other offices (since 20x150 + 50x30 = 4500) and the answer to the question is 20+30=50.
-Each executive office is 180 square meters, then the average of the remaining office is 60 square meters - and we have 20 executive offices and 15 other offices (since 20x180 + 15x60 = 4500) and the answer to the question is 20+15=35.
Combined, INSUFFICIENT
Final Answer: E
GMAT assassins aren't born, they're made,
Rich
