Is Y=0?

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Source: — Data Sufficiency |

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by ssmiles08 » Thu Jun 11, 2009 2:31 pm
IMO D.

Choice 1 says x is negative:

so |-x| = x

x-x = 0 = y

Sufficient.

Choice 2 says y < 1.

Y can be only be one of the two following possibilities: positive or 0

Since y<1, y must = 0.

Sufficient

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by tohellandback » Thu Jun 11, 2009 6:06 pm
My take D(after edit..ssmiles opened my eyes, Planning to mail him some japanese sake:)))
1) x<0
y=|x|+x
for x<0,y=0..so SUFFICIENT

2) y=0; for all x<0
y=2x; for all x>0
now y<1
so the values can be 0<=y<1, y can only be an integer so y=0
SUFF
Last edited by tohellandback on Thu Jun 11, 2009 6:20 pm, edited 1 time in total.
The powers of two are bloody impolite!!

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by ssmiles08 » Thu Jun 11, 2009 6:15 pm
tohellandback wrote: so the values can be 0<=y<1, last time I checked there were infinite numbers in that range..so INSUFF
Maybe I am missing something tohellandback, but it says y is an integer, so there is only 1 possible number right?

Please correct me if I am wrong

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by tohellandback » Thu Jun 11, 2009 6:18 pm
ssmiles08 wrote:
tohellandback wrote: so the values can be 0<=y<1, last time I checked there were infinite numbers in that range..so INSUFF
Maybe I am missing something tohellandback, but it says y is an integer, so there is only 1 possible number right?

Please correct me if I am wrong
ssmiles,
domo arigatou gozaimasu..
I guess I need more patience
alrite
I missed the integer part. You are right..
The powers of two are bloody impolite!!

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by ssmiles08 » Thu Jun 11, 2009 6:35 pm
tohellandback wrote:
ssmiles08 wrote:
tohellandback wrote: so the values can be 0<=y<1, last time I checked there were infinite numbers in that range..so INSUFF
Maybe I am missing something tohellandback, but it says y is an integer, so there is only 1 possible number right?

Please correct me if I am wrong
ssmiles,
domo arigatou gozaimasu..
I guess I need more patience
alrite
I missed the integer part. You are right..
No Problem :) I definitely could use some myself (both patience and sake! hah) :)