-
piyush2694
- Junior | Next Rank: 30 Posts
- Posts: 14
- Joined: Thu Dec 20, 2018 3:54 am
- Followed by:2 members
OA: Epiyush2694 wrote:Is x > y?
(1) x^2 < y
(2) x^(1/2) >y
Inequalities
This topic has expert replies
Source: Beat The GMAT — Quantitative Reasoning |
-
piyush2694
- Junior | Next Rank: 30 Posts
- Posts: 14
- Joined: Thu Dec 20, 2018 3:54 am
- Followed by:2 members
Statement 1:
if x is 2, y=5, then 4<5, here 2<5, that is x<y
if x is 0.5, y=0.3, then 0.25<0.3, here 0.5>0.3, that is x>y
So we cant conclude that if x>y of x<y
Statement 2:
Here x>=0, if square both sides of the inequality,
we have x>y^2, then x>y
Thus, statement 2 only is sufficient.
Please let me know if this is correct
if x is 2, y=5, then 4<5, here 2<5, that is x<y
if x is 0.5, y=0.3, then 0.25<0.3, here 0.5>0.3, that is x>y
So we cant conclude that if x>y of x<y
Statement 2:
Here x>=0, if square both sides of the inequality,
we have x>y^2, then x>y
Thus, statement 2 only is sufficient.
Please let me know if this is correct
-
fskilnik@GMATH
- GMAT Instructor
- Posts: 1449
- Joined: Sat Oct 09, 2010 2:16 pm
- Thanked: 59 times
- Followed by:33 members
$$x\,\,\mathop > \limits^? \,\,y$$piyush2694 wrote:Is x > y?
(1) x^2 < y
(2) x^(1/2) >y
$$\left( {1 + 2} \right)\,\,\,\,{x^2} < y < \sqrt x \,\,\,\,\,\,\left\{ \matrix{
\,{\rm{Take}}\,\,\left( {x;y} \right) = \left( {{1 \over 4};{1 \over 3}} \right)\,\,\,\, \Rightarrow \,\,\,\left\langle {{\rm{NO}}} \right\rangle \,\, \hfill \cr
\,{\rm{Take}}\,\,\left( {x;y} \right) = \left( {{1 \over 4};{1 \over 5}} \right)\,\,\,\, \Rightarrow \,\,\,\left\langle {{\rm{YES}}} \right\rangle \,\, \hfill \cr} \right.\,\,\,\,\,\,\, \Rightarrow \,\,\,\,\,\,\,\left( {\rm{E}} \right)$$
This solution follows the notations and rationale taught in the GMATH method.
Regards,
Fabio.
Fabio Skilnik :: GMATH method creator ( Math for the GMAT)
English-speakers :: https://www.gmath.net
Portuguese-speakers :: https://www.gmath.com.br
English-speakers :: https://www.gmath.net
Portuguese-speakers :: https://www.gmath.com.br
-
fskilnik@GMATH
- GMAT Instructor
- Posts: 1449
- Joined: Sat Oct 09, 2010 2:16 pm
- Thanked: 59 times
- Followed by:33 members
It´s not. Your mistake is the implication show in red.zzqtd wrote:Statement 1:
if x is 2, y=5, then 4<5, here 2<5, that is x<y
if x is 0.5, y=0.3, then 0.25<0.3, here 0.5>0.3, that is x>y
So we cant conclude that if x>y of x<y
Statement 2:
Here x>=0, if square both sides of the inequality,
we have x>y^2, then x>y
Thus, statement 2 only is sufficient.
Please let me know if this is correct
$$\left( {x;y} \right) = \left( {{1 \over 4};{1 \over 3}} \right)\,\,\,\,\,\, \Rightarrow \,\,\,\,\left\{ \matrix{
\,x > {y^2}\,\,\,{\rm{true}} \hfill \cr
\,x > y\,\,\,\,\,{\rm{false}} \hfill \cr} \right.\,\,$$
Regards,
Fabio.
Fabio Skilnik :: GMATH method creator ( Math for the GMAT)
English-speakers :: https://www.gmath.net
Portuguese-speakers :: https://www.gmath.com.br
English-speakers :: https://www.gmath.net
Portuguese-speakers :: https://www.gmath.com.br
