Data Sufficiency

1. If x,y,m and n are positive integers, where m>n, is x^m/y^n>1?
(1)x>y
(2)x^m>y^m

2.If x and y are positive integers, m and n are integers, where m>n, is x^m/y^n>1
(1)x>y
(2)x^m>y^m

3.If x and y are non zero integers and m and n are positive integers, where m>n is x^m/y^n>1?
(1)x>y
(2)x^m>y^m

4.If x,y and z are non zero integers, m and n are positive even integers, where m>n, is x^m*z/y^n>1?
(1)|z|>|x|>|y|
(2)x^m>y^n/z

Sorry but I don't have the OAs for any of them. Detailed explanations would be appreciated. Many Thanks.

1. If x,y,m and n are positive integers, where m>n, is x^m/y^n>1?
(1)x>y
(2)x^m>y^n

IMO:D

2.If x and y are positive integers, m and n are integers, where m>n, is x^m/y^n>1
(1)x>y
(2)x^m>y^n

IMO:B

3.If x and y are non zero integers and m and n are positive integers, where m>n is x^m/y^n>1?
(1)x>y
(2)x^m>y^n

IMO:B

4.If x,y and z are non zero integers, m and n are positive even integers, where m>n, is x^m*z/y^n>1?
(1)|z|>|x|>|y|
(2)x^m>y^n/z

IMO:D

I disagree with GmatKiss on #3. IMO E

x & y are non zero integers, m & n are positive integers m>n

1.)x>y;
-choose x = -2, y = -3, also choose m = 2, n = 1. x^m/y^n = 4/-3, x^m/y^n < 1
-choose x = -2, y = -3, also choose m = 4, n = 2. x^m/y^n = 16/9, x^m/y^n > 1
insufficient.

2.)x^m>y^n
-choose x = -2, y = -3, also choose m = 2, n = 1. x^m = 4, y^n = -3, x^m/y^n < 1
-choose x = -2, y = -3, also choose m = 4, n = 2. x^m = 16, y^n = 9, x^m/y^n > 1
insufficient.

Combining these 2 statements yields no useful information (noted as we used the exact same data sets to show both statements are insufficient.)

Therefore, IMO E

GmatKiss wrote:3.If x and y are non zero integers and m and n are positive integers, where m>n is x^m/y^n>1?
(1)x>y
(2)x^m>y^n

IMO:B

[/quote]

Dude, whats the source looks like good questions.

HeintzC2 wrote:I disagree with GmatKiss on #3. IMO E

x & y are non zero integers, m & n are positive integers m>n

1.)x>y;
-choose x = -2, y = -3, also choose m = 2, n = 1. x^m/y^n = 4/-3, x^m/y^n < 1
-choose x = -2, y = -3, also choose m = 4, n = 2. x^m/y^n = 16/9, x^m/y^n > 1
insufficient.

2.)x^m>y^n
-choose x = -2, y = -3, also choose m = 2, n = 1. x^m = 4, y^n = -3, x^m/y^n < 1
-choose x = -2, y = -3, also choose m = 4, n = 2. x^m = 16, y^n = 9, x^m/y^n > 1
insufficient.

Combining these 2 statements yields no useful information (noted as we used the exact same data sets to show both statements are insufficient.)

Therefore, IMO E

GmatKiss wrote:3.If x and y are non zero integers and m and n are positive integers, where m>n is x^m/y^n>1?
(1)x>y
(2)x^m>y^n

IMO:B

[/quote]
Actual Question is : 3.If x and y are non zero integers and m and n are positive integers, where m>n is x^m/y^n>1?
(1)x>y
(2)x^m>y^m

Ans is C!

By using the statement 1, we can conclude statement 2, X^m > y^m ...that's sufficient to ans.

n@resh wrote: Actual Question is : 3.If x and y are non zero integers and m and n are positive integers, where m>n is x^m/y^n>1?
(1)x>y
(2)x^m>y^m

Ans is C!

By using the statement 1, we can conclude statement 2, X^m > y^m ...that's sufficient to ans.

Hi,
The question has been changed one day after HeintzC2 posted. Earlier, statement(2) was x^m>y^n.
Anyway, coming to the modified version of Q3, I don't think it is C.
From(1):
if x=2, y=1, m=2,n=1, x^m/y^n = 4>1
if x=2, y=-1, m=2,n=1, x^m/y^n = -4<1
Not sufficient

From(2):
Use the same set
Not sufficient

Both(1) and (2):
Same set
Not sufficient

Hence, E

1. If x,y,m and n are positive integers, where m>n, is x^m/y^n>1?
(1)x>y
(2)x^m>y^m

From(1):
x>y
So, x^m > y^m
m>n. So, y^m >= y^n
So, x^m > y^n
Sufficient

From(2):
x^m > y^m
As m>n, y^m >= y^n.
So, x^m > y^n
Sufficient

Hence, D

2.If x and y are positive integers, m and n are integers, where m>n, is x^m/y^n>1
(1)x>y
(2)x^m>y^m

From(1):
if x=2, y=1, m=2, n=1, x^m/y^n = 4>1
if x=2, y=1, m=-1 n=-2, x^m/y^n = 1/2<1
Not Sufficient

From(2):
x^m>y^m
As y>0, and m>n
y^m >= y^n
So, x^m > y^n
As y is positive, y^n is always positive.
So, multiplying by 1/y^n will not change sign.
So, x^m/y^n > 1
Sufficient

Hence, B

4.If x,y and z are non zero integers, m and n are positive even integers, where m>n, is x^m*z/y^n>1?
(1)|z|>|x|>|y|
(2)x^m>y^n/z

From(1):
if x=2,y=1,z=4, m=4,n=2, x^m*z/y^n = 2^16>1
if x=2,y=1,z=-4, m=4,n=2, x^m*z/y^n = 2^-16<1
Not sufficient

From(2):
Same set
Not sufficient

Both (1)and (2):
Not sufficient

Hence, E

I hope I haven't made any silly mistakes in my posts. If I have made any, please let me know.