Are all of the numbers in a certain list of 15 numbers equal

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Are all of the numbers in a certain list of 15 numbers equal?
(1) The sum of all the numbers in the list is 60.
(2) The sum of any 3 numbers in the list is 12.

OG ANSWER IS B

STATEMENT 1: THIS ONLY SAYS THE SUM OF THE 15 NUMBERS IS 60 ... THE #'S COULD BE ALL DIFFERENT BUT STILL ADD UP TO 60 {8, 4 , 3 ...ETC} OR ... THE NUMBERS HERE CAN ALL BE 4 .... YES & NO = NOT SUFF!!

STATEMENT 2: THE SUM OF ANY 3 NUMBERS IN THE LIST IS 12 ...

JUST WANTED TO GET THIS WORDING CORRECT ... PLEASE CONFIRM ...

IN ORDER FOR EVERY 3 NUMBERS IN THE LIST TO = 12, EVERY NUMBER MUST BE EQUAL. (HENCE ... LIST 3 ,4, 7, 2 ... = 60 BUT NOT EVERY 3 NUMBERS IN THIS SET IS EQUAL (IE 3 + 4 + 2 DOES NOT EQUAL 4 + 2 + 7) ... ANY 3 NUMBERS MAKES EACH NUMBER 4 EVERYTIME!
Source: — Data Sufficiency |

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by gmatboost » Sun Aug 07, 2011 11:27 pm
I would just say that you should be careful not to take St 1 into account when working on St 2. Your answer is right, but you should not justify using any of the info from St 1 (in this case, the fact that the sum is 60).
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by GmatKiss » Mon Aug 08, 2011 12:26 am
1. Not sufficient

2. sum of any 3 numbers is 12.
from given we know all the no.s are the same.
x+y+z=12 ; x=y=z=4 and 4*15=60 (sufficient)

IMO:B

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by GMATGuruNY » Mon Aug 08, 2011 3:29 am
I posted an explanation for statement 2 here:

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