IMO (C)
Statement 1: 2x > y
Lets say x = 1/2 and y = 3/4. Therefore, x < y
Lets say x = 1 and y = 1. Therefore x = y
Lets say x = 2 and y = 1. Therefore x > y
Above all three stated statements are contradicting each other.
Therefore, statement 1 -> Insufficient.
Statement 2: y < 0
No info about x. Hence statement 2 -> Insufficient.
Lets take both statement together.
x >= 0, y < 0. Therefore, x > y
x > -(1/3), y = -1, therefore x > y
x = -(1/2), y = -(1/2). => Not possible (It invalidates the 1st statement)
Try any other negative combination which satisfy both statements, X will always greater than Y.
Hence, both statements together are sufficient. Choose (C).
DS Question
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Source: Beat The GMAT — Data Sufficiency |
That's what I said in my previous post,maihuna wrote:Itoo C why?
so how it will turn out to be: IF Y = -4 X > -2 i.e. X = -1 that way x will be greater than y
Daisy wrote: Try any other negative combination which satisfy both statements, X will always greater than Y.
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logitech
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We are trying to prove whether X-Y > 0giatch wrote:Is x> y?
1. 2x> y
2. y <0
Anyone have any idea of how you go about solving this? Like how would you pick numbers to get a solution? or is there some method to approach this question?
1. 2x> y
2x - y > 0
We can simplfy this to X-Y so insuf
2. y <0
No information about X - INSUF
TOGETHER
2x - y > 0
- y > 0 [ Note the sign change ]
Let's add these two equations:
2x - 2y > 0
OR
X - Y > 0 Tataaam!!!
Hence, C
LGTCH
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logitech
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BE CAREFUL!!giatch wrote:1. 2x> y
2x - y > 0
We can simplfy this to X-Y so insuf
---------
How do you simply 2x-y to x-y? Or do you mean, you cannot simply, so insufficient?
X=2 Y =3
2x - Y = 4-3 = 1 > 0
X-Y = 2-3 = -1 < 0
ONCE AGAIN!! BE CAREFUL!!
LGTCH
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"DON'T LET ANYONE STEAL YOUR DREAM!"
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"DON'T LET ANYONE STEAL YOUR DREAM!"
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cramya
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Giatch,
Here's one way:
Q: Is x>y (u can rephrase this as Is x-y>0 then prove it like some of the other solutions have shown but I will leave it as is to illustrate it by picking numbers
Note: x and y does not have to be integers since its not given
Since u had asked about picking numbers here is one way to solve by picking numbers
Stmt I
2x > y
Is x >y
x=1/2 y=9/10
2x > y but x > y NO
x=10 y=1
2x>y and x>y YES
2 different answers(YES/NO) INSUFF
Stmt II
y<0
No info about x
INSUFF
Together
2x>y (1)
y<0 or 0>y (2)
Add Inequalities facing same direction((1) and (2)):
2x+0>y+y
2x>2y
Divide by 2 on both sides(inequality does not change since we are dividing by a positive number 2)
x>y
SUFF
Choose C)
Here's one way:
Q: Is x>y (u can rephrase this as Is x-y>0 then prove it like some of the other solutions have shown but I will leave it as is to illustrate it by picking numbers
Note: x and y does not have to be integers since its not given
Since u had asked about picking numbers here is one way to solve by picking numbers
Stmt I
2x > y
Is x >y
x=1/2 y=9/10
2x > y but x > y NO
x=10 y=1
2x>y and x>y YES
2 different answers(YES/NO) INSUFF
Stmt II
y<0
No info about x
INSUFF
Together
2x>y (1)
y<0 or 0>y (2)
Add Inequalities facing same direction((1) and (2)):
2x+0>y+y
2x>2y
Divide by 2 on both sides(inequality does not change since we are dividing by a positive number 2)
x>y
SUFF
Choose C)
thanks guys for the help..
i get it now..
i was having a hard time figuring out which numbers to use..
i suppose for questions like this, if it is not specified that the variables are integers, start by picking #'s like 1/2, etc.
out of curiosity, would you start the stem assuming that the equation is true and then work your way to see if it is? or start off as it being false and trying to see if the answers agree?
i get it now..
i was having a hard time figuring out which numbers to use..
i suppose for questions like this, if it is not specified that the variables are integers, start by picking #'s like 1/2, etc.
out of curiosity, would you start the stem assuming that the equation is true and then work your way to see if it is? or start off as it being false and trying to see if the answers agree?
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cramya
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out of curiosity, would you start the stem assuming that the equation is true and then work your way to see if it is? or start off as it being false and trying to see if the answers agree
Hope I understood your question.
The question stem is what we need to find based on the information given in the 2 statements. The real task is to check if the information given in each of the statements by itself or together (depending on how it goes ) are SUFFICIENT to find what we need to (i.e x>y in this problem)
Eg: We need to find if x>y possibly from the 2 statements given.
When we take each of the statements by itself first and then together if needed we have to prove that its either INSUFFICIENT OR SUFFICIENT to get a defnite answer for what asked in the question stem.
If its a find the value question (eg: what is the value of x) then we must be able to find one definite value for x.
If its a YES or NO question then we must get a DEFINITE YES OR A DEFNITE NO from the stmts etc...
Check this out on some basic info on how to approach DS questions. Its always good to elimnate choices and then work with remaining choices. This way u would be increasing the chaces of getting a question correct.
https://www.gmathacks.com/data-sufficien ... -test.html
Hope this helps! Let us know if u have more questions.
Regards,
Cramya
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ronniecoleman
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IMO C
x> y?
1. 2x> y
2. y <0
1) Picking postive numbers;
x = 1
y = 1
2x > y
but x = y
OUT
2) y < 0
x can be any number... OUT
togther...
------------------- ( y) ----------------------( 2x) ------------------(x) -----------------0
choose any value if 2x > y ( negatvie number line)
so x > y always ...
x> y?
1. 2x> y
2. y <0
1) Picking postive numbers;
x = 1
y = 1
2x > y
but x = y
OUT
2) y < 0
x can be any number... OUT
togther...
------------------- ( y) ----------------------( 2x) ------------------(x) -----------------0
choose any value if 2x > y ( negatvie number line)
so x > y always ...
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