Question: Jets Fans in a Dormitory

Comment on Jets Fans in a Dormitory

How did you get 5/12
gmat-admin's picture

Good question.

When we add the given fractions we get 7/12

So, up to that point, have have only accounted for 7/12 of the students. Since 7/12 + 5/12 = 12/12 = 1, we can conclude that, if 7/12 of the students are accounted for, then 5/12 of the students are NOT accounted for.

Does that help?


I am yet not able to understand how you got 5/12.

Is there an other explaination?
gmat-admin's picture

When we add 1/3 + 1/6 + 1/12, we are determining the proportion of students who are Jets fans, Bears fans or Raiders fans.

1/3 + 1/6 + 1/12 = 7/12
So, 7/12 of the students are Jets fans, Bears fans or Raiders fans
In other words, 7/12 of the students are NOT Dolphins fans.
This means the REMAINING 5/12 of the students ARE Dolphins fans.

Does that help?


Hi Brent, I got the answer in a different way, please let me know if this approach is ok to use for future questions.

5/12=30 thus 10/12=60 thus 1/12=6 thus 10/12+1/6+1/6=12/12=72
gmat-admin's picture

Ahhhh! Very nice reasoning, Luis!!

Just to be clear (for others reading this), Luis is saying that, if 5/12 of T = 30, then we can say that 10/12 of T = 60, which means 1/12 of T = 6.
Finally, if 1/12 of T = 6, then 12/12 of T = 72. In other words, T = 72.

"To determine which answer choice is closest to the number, we can subtract the number from each answer choice. The difference that is closest to zero will indicate the fraction that is closest to the number."

Should I add this strategy to my notebook?
gmat-admin's picture

Can you tell me what question this is related to?

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