Group Of Children

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Group Of Children

by money9111 » Wed Feb 17, 2010 1:02 pm
A group of 630 children is arranged in rows for a group photograph session. Each row contains three fewer children than the row in front of it. What number of rows is not possible?

A. 3
B. 4
C. 5
D. 6
E. 7

note - this is not an Official Guide Question - it's from Complore.com which is where many of the other questions are from that are being posted. I just wanted to let people out there know where a lot of the questions are from that they're answering. And before someone says "THIS IS COPY AND PASTED" I would like to tell everyone - YES IT IS... as are all of the other questions similar on here. Is there anything wrong with it? Well you be the judge. If this is the way people want to take the competition... well that's unfortunate. This will be my one and only post that's copy and pasted simply for the purpose of gaining posts for the contest. Any further Math/Verbal questions that I post are truly for my understanding!

Solution Copy and Pasted as well...

[spoiler]
Let n be the number of rows in the arrangement of the 630 children. If n is odd, the number of children in the middle row multiplied by n is 630. Thus, an odd value of
n is possible, only if n is a factor of 630.

So, n = 3, 5, 7 are possible.
For n = 4, the possible arrangement is 162, 159, 156 and 153.
Hence n = 6 is the only option left out and is not possible.
Note: For n - 6, we get numbers which are not integers.[/spoiler]
Last edited by money9111 on Wed Feb 17, 2010 1:06 pm, edited 2 times in total.
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by Osirus@VeritasPrep » Wed Feb 17, 2010 1:04 pm
You know that you posting the solution isn't going to stop harsh.champ and/or shashank from coming in here and posting the exact same thing..lol
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by Stuart@KaplanGMAT » Wed Feb 17, 2010 5:29 pm
osirus0830 wrote:You know that you posting the solution isn't going to stop harsh.champ and/or shashank from coming in here and posting the exact same thing..lol
It's actually better not to post the solution in the original post, since it discourages people from trying it on their own/coming up with different solutions.
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