x, y, and –1 is 1

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x, y, and –1 is 1

by sanju09 » Sun Feb 20, 2011 11:21 pm
What is the average (arithmetic mean) of x and y?

(1) The average (arithmetic mean) of (x + 1) and (y - 1) is equal to the average (arithmetic mean) of x and y.

(2) The average (arithmetic mean) of x, y, and -1 is 1.

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by coolly01 » Mon Feb 21, 2011 12:40 am
sanju09 wrote:What is the average (arithmetic mean) of x and y?

(1) The average (arithmetic mean) of (x + 1) and (y - 1) is equal to the average (arithmetic mean) of x and y.

(2) The average (arithmetic mean) of x, y, and -1 is 1.
Is it B. I'm new in this forum. I hope I can catch up with you guys

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by sanju09 » Mon Feb 21, 2011 1:27 am
coolly01 wrote:
sanju09 wrote:What is the average (arithmetic mean) of x and y?

(1) The average (arithmetic mean) of (x + 1) and (y - 1) is equal to the average (arithmetic mean) of x and y.

(2) The average (arithmetic mean) of x, y, and -1 is 1.
Is it B. I'm new in this forum. I hope I can catch up with you guys
Welcome with Congratulations, you are right, could you please explain your take on it?
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by Night reader » Mon Feb 21, 2011 1:34 am
@sanju you kidding us?
st(1) N/S the same as quest.stem
st(2) (x+y-1)/3=1 --> x+y=4 mean is 2 . Answer B
sanju09 wrote:What is the average (arithmetic mean) of x and y?

(1) The average (arithmetic mean) of (x + 1) and (y - 1) is equal to the average (arithmetic mean) of x and y.

(2) The average (arithmetic mean) of x, y, and -1 is 1.
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