Interesting GMATFix Problem-37

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Interesting GMATFix Problem-37

by arora007 » Thu Sep 23, 2010 9:56 am
If -1<z<0, which of the following expression has the second greatest value?
A)z
B)z^-3
C)z^-2
D)root(z^2)
E)z^2
can somebody explain if the root formula valid for choice D as per GMAT.
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by diebeatsthegmat » Thu Sep 23, 2010 10:48 am
arora007 wrote:If -1<z<0, which of the following expression has the second greatest value?
A)z
B)z^-3
C)z^-2
D)root(z^2)
E)z^2
can somebody explain if the root formula valid for choice D as per GMAT.
hehehehe, babe, the questions you posted are so tough hehehe
z is between -1 and 0 thus z must be negative so we can elimit c, d, E because it will give us a positive number of z
give z=-1/10 and -1/2 and -9/10 we will have z^3=1/1000 and -1/8 and -729/1000
the answer must be B
right, honey?

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by sanabk » Thu Sep 23, 2010 11:19 am
-1<z<0, Let z=-0.1

A)z=-0.1
B)z^-3=-1000
C)z^-2= 100
D)root(z^2)=|z|=|-0.1|=0.1
E)z^2=0.01

100>0.1>0.01>-0.1>-1000

The second greatest value is 0.1.
D

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by diebeatsthegmat » Thu Sep 23, 2010 11:30 am
sanabk wrote:-1<z<0, Let z=-0.1

A)z=-0.1
B)z^-3=-1000
C)z^-2= 100
D)root(z^2)=|z|=|-0.1|=0.1
E)z^2=0.01

100>0.1>0.01>-0.1>-1000

The second greatest value is 0.1.
D
hey man, 0.1>0

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by sanabk » Thu Sep 23, 2010 4:05 pm
Here z takes value between -1 and 0 (-1<z<0) and the question is asking the second greatest value and this value need not take value between the -1<z<0 interval.

Correct me if I am wrong.

Thanks!

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by diebeatsthegmat » Thu Sep 23, 2010 10:23 pm
sanabk wrote:Here z takes value between -1 and 0 (-1<z<0) and the question is asking the second greatest value and this value need not take value between the -1<z<0 interval.

Correct me if I am wrong.

Thanks!
i think we must find the greatest value of z which is between -1 and 0 thus i supposed that it must be a negative number which is closer to 0
am i right?
what is the answer mr babe Arora?

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by diebeatsthegmat » Thu Sep 23, 2010 10:23 pm
arora007 wrote:If -1<z<0, which of the following expression has the second greatest value?
A)z
B)z^-3
C)z^-2
D)root(z^2)
E)z^2
can somebody explain if the root formula valid for choice D as per GMAT.
what is the answer mr babe Arora?

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by arora007 » Fri Sep 24, 2010 1:27 am
diebeatsthegmat wrote:
arora007 wrote:If -1<z<0, which of the following expression has the second greatest value?
A)z
B)z^-3
C)z^-2
D)root(z^2)
E)z^2
can somebody explain if the root formula valid for choice D as per GMAT.
hehehehe, babe, the questions you posted are so tough hehehe
z is between -1 and 0 thus z must be negative so we can elimit c, d, E because it will give us a positive number of z
give z=-1/10 and -1/2 and -9/10 we will have z^3=1/1000 and -1/8 and -729/1000
the answer must be B
right, honey?
Yeah Sugarbuns... this is a tough problem... ;-)
sanabk is correct, D is the OA.
but dear... we have to get the act right
see z^3=1/1000 should have been -1/1000
if z is negative z^3 or Z^odd integer would be negative only and Z^even interger would positive.

In this questions what I cont under stand is...
I hope sanabk can explain me about why

D)root(z^2)=|z|=|-0.1|=0.1
does root of the square of the value not have to be orignal number
how can we assume it to be modulus?? or is it as per mathematical formula??
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by diebeatsthegmat » Fri Sep 24, 2010 5:26 am
arora007 wrote:
diebeatsthegmat wrote:
arora007 wrote:If -1<z<0, which of the following expression has the second greatest value?
A)z
B)z^-3
C)z^-2
D)root(z^2)
E)z^2
can somebody explain if the root formula valid for choice D as per GMAT.
hehehehe, babe, the questions you posted are so tough hehehe
z is between -1 and 0 thus z must be negative so we can elimit c, d, E because it will give us a positive number of z
give z=-1/10 and -1/2 and -9/10 we will have z^3=1/1000 and -1/8 and -729/1000
the answer must be B
right, honey?
Yeah Sugarbuns... this is a tough problem... ;-)
sanabk is correct, D is the OA.
but dear... we have to get the act right
see z^3=1/1000 should have been -1/1000
if z is negative z^3 or Z^odd integer would be negative only and Z^even interger would positive.

In this questions what I cont under stand is...
I hope sanabk can explain me about why

D)root(z^2)=|z|=|-0.1|=0.1
does root of the square of the value not have to be orignal number
how can we assume it to be modulus?? or is it as per mathematical formula??
ohhh it asked to find the greatest number ( from choice A to choice E) which is fit the condition -1<z<0
ohh english!!!!
if its about that, agree D is the rigth answer
root of the square of the value cant be original number.
i meant square root of z^2 must be absolute z ( squrt(z^2)=|z| because z is now is unknown number
its the rule said in OG ( OG11 page 126)

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by arora007 » Fri Sep 24, 2010 9:54 am
Thanks for ( OG11 page 126) , If only thanks could mean something else in English!! ;-)
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