. - DS
are x and y both positive?
(1) 2x - 2y = 1
(2) x/y > 1
Why is the answer C?
when we combine 1 and 2
X could be 0 when y is -1/2
so X is non-negative and non-positive whereas Y is negative
therefore we could have x and y both positive as well as X as 0 and y negative, and still satisfy the X>y and x-y=1/2
need help with this simple question
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from stament 1)2x-2y=1 dividing both side by 2
we have x-y=1/2
so this is not sufficient
from 2)x/y>1
so we can say x>y
from 1&2 we can say x and y are positive as xis greater than y and there difference is positive
to cross check you can plug some numbers and c for yourself
we have x-y=1/2
so this is not sufficient
from 2)x/y>1
so we can say x>y
from 1&2 we can say x and y are positive as xis greater than y and there difference is positive
to cross check you can plug some numbers and c for yourself
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Buddy,
do you agree 0 is greater than -1/2?
so if x = 0 and y = -1/2
x-y= 1/2
so here o is non negative or non positive whereas y is negative
do you agree 0 is greater than -1/2?
so if x = 0 and y = -1/2
x-y= 1/2
so here o is non negative or non positive whereas y is negative
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The question states are x and y positive?
The answer is both no and yes.
therefore the solution should be E
We can have 0 for x and -1/2 for y. Also x could be 1 and y = 1/2. In both cases X is greater than y but x is not necessarily positive.
The answer is both no and yes.
therefore the solution should be E
We can have 0 for x and -1/2 for y. Also x could be 1 and y = 1/2. In both cases X is greater than y but x is not necessarily positive.
If x = 0, and y = -1/2 then x/y is not greater than one. Zero divided by anything is still zero. You took the second constraint to mean that x is greater than y, but this is not necessarily true.
What if both x and y are negative?
Such as, x = -15, y =-10. Then x would be less than y, but x/y would still be greater than 1.
What if both x and y are negative?
Such as, x = -15, y =-10. Then x would be less than y, but x/y would still be greater than 1.
________
GmatPrep 1: 770, Q50 V44
Kaplan CAT 1: 660, Q44, V41
Kaplan CAT 2: 670, Q50, V37
Kapaln CAT 3: 500, Q50, V8
GmatPrep 2: 770, Q50, V45
GmatPrep 1: 770, Q50 V44
Kaplan CAT 1: 660, Q44, V41
Kaplan CAT 2: 670, Q50, V37
Kapaln CAT 3: 500, Q50, V8
GmatPrep 2: 770, Q50, V45