Number Operations???

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Number Operations???

by vladmire » Sat Dec 06, 2008 4:58 pm
If x - y >10, is x-y > x+y

(1) x = 8
(2) y= -20

a.1 suff
b. 2 suff
c. both
d. each alone
e. neither

I can get that y< -2 for (1) now how do I use that to help answer the question
Source: — Data Sufficiency |

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by cramya » Sat Dec 06, 2008 5:17 pm
Is the answer D)

x - y >10

Stmt I

y<-2

y is negative since x is positibve x-y > x+y

SUFF

Stmt II

y= -20


X-Y>10

X-(-20) > 10
X>-10

x=-9

x-y>x+y

x=100 x-y still greater than x+y (ANY VALUE OF X > -10 X-Y WILL BE GREATER THAN X+Y)

SUFF

D)

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by dmateer25 » Sat Dec 06, 2008 5:28 pm
I did the problem just as cramya did. Another vote for D.

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Re: Number Operations???

by logitech » Sat Dec 06, 2008 5:29 pm
Check below:
Last edited by logitech on Sat Dec 06, 2008 5:32 pm, edited 1 time in total.
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Re: Number Operations???

by logitech » Sat Dec 06, 2008 5:31 pm
vladmire wrote:If x - y >10, is x-y > x+y

(1) x = 8
(2) y= -20

a.1 suff
b. 2 suff
c. both
d. each alone
e. neither

I can get that y< -2 for (1) now how do I use that to help answer the question
Is x-y > x+y ?

So it actually means Is 2y<0 OR is Y < 0


(1) x = 8

x - y >10

8-y>10 So Y <-2 BINGO!


(2) y= -20

Duh!!

Choose D and smile

:D
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by Zipper » Sat Dec 06, 2008 5:38 pm
I've had a little different approach:
x-y > x+y <=> -y>y

so as cramya said:

1. y<-2 //suff
2. y=-20 //suff

Hence, D