A certain language school has two classes for children.

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A certain language school has two classes for children. Is the range of ages, in years, of the children in the first class equal to the range of ages, in years, of the children in the second class?

(1) In each class, the number of children is 18 and the age of the youngest child is 8 years.
(2) In each class, the average (arithmetic mean) age of the children is 10 years.

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by GMATGuruNY » Wed Jul 27, 2016 3:15 am
NandishSS wrote:A certain language school has two classes for children. Is the range of ages, in years, of the children in the first class equal to the range of ages, in years, of the children in the second class?

(1) In each class, the number of children is 18 and the age of the youngest child is 8 years.
(2) In each class, the average (arithmetic mean) age of the children is 10 years.
Range = oldest - youngest.

Statements combined:
Sum of the ages in each class = (number of children)(average age per child) = 18*10 = 180.
Sum of the ages of the 17 OLDEST children in each class = (sum of all of the ages in each class) - (age of youngest child in each class) = 180-8 = 172.
Since there is no way to determine the age of the oldest child in each class, the range for each class cannot be determined.
INSUFFICIENT.

The correct answer is E.
Last edited by GMATGuruNY on Fri Aug 19, 2016 9:31 pm, edited 1 time in total.
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by Matt@VeritasPrep » Fri Aug 19, 2016 3:29 pm
GMATGuruNY wrote: Range = oldest = youngest.
The older I get, the more I wish this equation were true :)

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by GMATGuruNY » Fri Aug 19, 2016 9:35 pm
Matt@VeritasPrep wrote:
GMATGuruNY wrote: oldest = youngest.
The older I get, the more I wish this equation were true :)
Good catch.
Fixed the typo.
That said, I stand by the validity of the equation above.
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