Whenever you encounter a quantitative question with answer choices, be sure to SCAN the answer choices before performing any calculations. In many cases, the answer choices provide important clues regarding how to best solve the question.
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Comment on Jets Fans in a Dormitory
How you got the 5/12 ?
If we've accounted for 5/12
If we've accounted for 5/12 of the students, then 7/12 of the students are unaccounted for.
Likewise, if 2/5 of a population are female, then we can conclude that 3/5 of the population are male.
I made the mistake of
This is still a multiplying
This is still a multiplying situation, except we don't really need to write it as such.
For example, we can take "1/3 of the students are Jets fans" and write: (1/3)T = # of Jets fans (where T = TOTAL number of students)
Likewise, we can take "1/6 of the students are Bears fans" and write: (1/6)T = # of Bears fans
And (1/12)T = # of Dolphins fans
So, the number of fans accounted for = (1/3)T + (1/6)T + (1/12)T
= (7/12)T
And so on...
Does that help?
I converted the fractions to
1/3 --> 33.33%
1/6 --> 16.66%
1/12--> 0.08%
For a total of approx 51% of Jets', Bears' an Raiders'fans. The rest (49%) is 30 Dolphins' fans, which, adding up, is closer to a total of 60 than 72.
Therefore, choice A (60) was more approximate to be the correct answer. Where did I go wrong here?
Great approach!
Great approach!
The only problem is here: 1/12--> 0.08%
1/12 ≈ 0.08 ≈ 8% (not 0.08%)
Cheers,
Brent
Hey,
I am not clear in the second approach. how did we ended up multiplying entire expression by 12? Can you please elaborate on this?
Good question.
Good question.
Once we have the equation (1/3)T + (1/6)T + (1/12)T + 30 = T, we want to eliminate the fractions.
One way to do this is to multiply both sides of the equation by the least common multiple of the three denominators (3, 6, and 12)
So, I multiplied both sides of the equation by 12.
For more on the technique of eliminating fractions, check out this video: https://www.greenlighttestprep.com/module/gre-algebra-and-equation-solvi...
Fantastic, thank you!