Is x > y?
(1) root of x > y
(2) x^3 > y
c, but I think it shld be e
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nikhilagrawal
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parallel_chase
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Statement I & II are clearly insufficient alone.nikhilagrawal wrote:Is x > y?
(1) root of x > y
(2) x^3 > y
c, but I think it shld be e
Combining I & II
if x is a positive integer
x^3 > x > sqrtx, therefore if sqrt x is greater than y, x will also be greater than y.
if x is a negative integer.
We cannot have this case because, sqrt x will always be positive.
if x is less than 1 and greater than 0
sqrtx > x > x^3, if x^3 is greater than y, then x will certainly be greater than y.
Sufficient.
Hence C.
Hope this helps. Let me know if you still have any doubts.
No rest for the Wicked....
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lunarpower
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very well done. note the crucially important TAKEAWAY from this problem:parallel_chase wrote:Statement I & II are clearly insufficient alone.nikhilagrawal wrote:Is x > y?
(1) root of x > y
(2) x^3 > y
c, but I think it shld be e
Combining I & II
if x is a positive integer
x^3 > x > sqrtx, therefore if sqrt x is greater than y, x will also be greater than y.
if x is a negative integer.
We cannot have this case because, sqrt x will always be positive.
if x is less than 1 and greater than 0
sqrtx > x > x^3, if x^3 is greater than y, then x will certainly be greater than y.
Sufficient.
Hence C.
Hope this helps. Let me know if you still have any doubts.
TAKEAWAY: if you see comparison of different powers/roots of a variable, then you should consider both POS/NEG (if appropriate) and LESS THAN/GREATER THAN 1.
you'll be able to resolve most questions of this type by splitting into these cases, even if you don't fully understand the theory behind the problem.
Ron has been teaching various standardized tests for 20 years.
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Pueden hacerle preguntas a Ron en castellano
Potete chiedere domande a Ron in italiano
On peut poser des questions à Ron en français
Voit esittää kysymyksiä Ron:lle myös suomeksi
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Quand on se sent bien dans un vêtement, tout peut arriver. Un bon vêtement, c'est un passeport pour le bonheur.
Yves Saint-Laurent
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cramya
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Arun,
I dont think there is a comprehensive link withtakeways.
My suggestion is to start making your own flash cards when you read through the posts and see concepts explained. However there is flash card with quant formulas made by Eric(search for it or if I find it will send u)
Hoping Parallel Chase and Ron dont mind
Eg: The takeawy from what parallel chase said would be
if x is a positive integer
x^3 > x > sqrtx, therefore if sqrt x is greater than y, x will also be greater than y.
Eg:x =2
if x is less than 1 and greater than 0
sqrtx > x > x^3, if x^3
eg:x=1/4
The takeaway from Ron's statement is in bold
I was missing a lot of ds question when I started (I miss some now too) since I did not consider what Ron said(taking negative values or values between 0 and 1 etc...)
For example when a problem does not mention x/y as integers fractions come in to play big time. Also echoing Ron's statement considering negative and positive values i.e if the problem says integers and does not specifically say positive integers
Good luck.
I dont think there is a comprehensive link withtakeways.
My suggestion is to start making your own flash cards when you read through the posts and see concepts explained. However there is flash card with quant formulas made by Eric(search for it or if I find it will send u)
Hoping Parallel Chase and Ron dont mind
Eg: The takeawy from what parallel chase said would be
if x is a positive integer
x^3 > x > sqrtx, therefore if sqrt x is greater than y, x will also be greater than y.
Eg:x =2
if x is less than 1 and greater than 0
sqrtx > x > x^3, if x^3
eg:x=1/4
The takeaway from Ron's statement is in bold
I was missing a lot of ds question when I started (I miss some now too) since I did not consider what Ron said(taking negative values or values between 0 and 1 etc...)
For example when a problem does not mention x/y as integers fractions come in to play big time. Also echoing Ron's statement considering negative and positive values i.e if the problem says integers and does not specifically say positive integers
Good luck.
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cramya
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I was missing a lot of ds question when I started (I miss some now too) since I did not consider what Ron said(taking negative values or values between 0 and 1 etc.. in to consideration to determine SUFFICIENCY.)
For example when a problem does not mention x/y as integers fractions come in to play big time(I.E u need to check for these 2 before u confirm a choice from A-E). Also echoing Ron's statement considering negative and positive values i.e if the problem says integers and does not specifically say positive integers
Good luck.
For example when a problem does not mention x/y as integers fractions come in to play big time(I.E u need to check for these 2 before u confirm a choice from A-E). Also echoing Ron's statement considering negative and positive values i.e if the problem says integers and does not specifically say positive integers
Good luck.
