If x and y are integers, is x less than y ?

Question

(1) The cube of x is less than the cube of y.

(2) The square of x is less than the square y.

Raksat · Answer

IMO the answer should be A
from statement 1 :
x^3 < y^3
basically it says x<y (sign doesn't have the effect) hence sufficient
From statement 2
x^2 < y^2
consider 4<9
hence 2<3 ( yes)
but -2>-3(no)... insufficient
answer : A

akadiyan · Answer

If x and y are integers, is x less than y ?

(a) The cube of x is less than the cube of y. 
- This option works well with both positive and negative values. If X^3 < Y^3 , then X < Y. - Sufficient.

(b) The square of x is less than the square y. 
If the x and y are negative values, then square of X is not always less than square of Y. - Not Sufficient.

Ans - Option A

gmatexam439 · Answer

IMO A Stmt 1: x^3 < y^3 => x^3 - y^3 <0 => (x-y)( x^2 +y^2 +xy)<0; Now, ( x^2 + y^2 +xy) will be >0 Thus, x-y<0 => x (x+y)(x-y)<0; Now either could be <0; Insufficient

GMATBusters · Answer

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If x and y are integers, is x less than y ?

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