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M22-09

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M22-09 [#permalink]

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What is the mean age of all students of the city's schools?


(1) The average age of the students in each of the city's schools is 12

(2) The number of students in each of the city's schools is 70
[Reveal] Spoiler: OA

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New post 16 Sep 2014, 01:16
Official Solution:


Statement (1) by itself is sufficient. If \(N1, N2, ..., Nk\) are the respective school populations, the mean is \(\frac{12N1 + ... + 12Nk}{N1 + ... + Nk} = 12\).

Statement (2) by itself is insufficient. S2 says nothing about the age of the students.


Answer: A
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Re M22-09 [#permalink]

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New post 05 Mar 2016, 03:55
I think this is a poor-quality question and I don't agree with the explanation. the question asks for mean not average

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Re: M22-09 [#permalink]

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New post 05 Mar 2016, 04:11
deospaima wrote:
I think this is a poor-quality question and I don't agree with the explanation. the question asks for mean not average


hi deospaima,
average age is the same as MEAN age..
there are three terms in STATISTICS..
MEAN= this is same as AVERAGE
MEDIAN= the central value when the numbers, here ages, are arranged in ascending order..
MODE= the number with max repetition..

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Re: M22-09 [#permalink]

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New post 11 Aug 2017, 03:49
can someone provide a detailed explanation. :|

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Re: M22-09   [#permalink] 11 Aug 2017, 04:00
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