Does x-y = 200 ?
(1) x=10^2
(2) x=100 and y=-100
Seems very easy, don't understand why choice 1 is incorrect ?
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heshamelaziry
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tohellandback
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well,
1 says nothing about Y . thats why 1 is incorrect
for y=-100, x-y will be 200
for y=any other value it x-y will not be 200. Thats why NOT SUFF
2) is SUFF
1 says nothing about Y . thats why 1 is incorrect
for y=-100, x-y will be 200
for y=any other value it x-y will not be 200. Thats why NOT SUFF
2) is SUFF
The powers of two are bloody impolite!!
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grockit_jake
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Without an explanation for y, you can't know x - y. (1) is not sufficient because you are missing information on how to find y.
