There are a certain number of male and female students in a classroom.

Question

There are a certain number of male and female students in a classroom. The weights of the male students range from 80 kg to 85 kg. The weights of the female students range from 70 kg to 75 kg. What is the average (arithmetic mean) weight of all the students in the classroom? All weights are rounded to the nearest 1 kg.

(1) No two students weigh the same.

(2) The number of male students is equal to the number of female students.

conquerthegmat · Answer

1) Not enough
2) Not enough
combined:
The weight can be 80.1, 80.2, 80.3, ...., so it still cannot be answered

werty_123 · Answer

Bunuel  ,  karishma  ,  GMATNinja 
No two students weigh the same.

Can we infer that all students have different weights? If thats the case and the questions says All weights are rounded to the nearest 1 kg
, then it mean there are only 6 students in total. Hence, A is enough to answer

Bunuel · Answer

"No two students weigh the same" means that every student has a unique weight. However, it does not mean there are only 6 students, because the given weight ranges do not require one student per integer value. There could be fewer students, as long as each has a distinct weight within the range. For example, there can be a case where there are two male students, one weighing 80 kg and the other 85 kg.

So, statement (1) alone is not sufficient.

So, statement (1) alone is not sufficient.

jade529415 · Answer

“all weights are rounded to the nearest 1kg ” does not mean that they are integers.

PeachSnapple1 · Answer

The prompt said     and    . Kinda unambiguous. Are the weights of the students considered before or after rounding up? But in either case, the answer is E because we don't know the exact number of students.

Morina · Answer

Statement 1 is NS 
But Statement 2 : sin we know that 80<M<85 then m can take values from 81to 84 which the Average will be 82.5~83Kg same for Women ~73K and since both M=w then we can sum (73+83)/2 then we have the average of all students ? so its sufficient. is that correct ?

Bunuel · Answer

No, that reasoning is incorrect.

Statement (2) says the number of male and female students is the same, but it does  not  say that the weights are evenly distributed across each range. The male weights could all cluster near 80 or near 85, and the same for females near 70 or near 75.

There are a certain number of male and female students in a classroom.

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There are a certain number of male and female students in a classroom.

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

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