GMAT PREP QUESTION

This topic has expert replies
Newbie | Next Rank: 10 Posts
Posts: 8
Joined: Sat Jun 16, 2007 7:47 am

GMAT PREP QUESTION

by charmingirl8 » Wed Sep 05, 2007 7:07 pm
Can anyone help? The answer is C but i don't agree with it as for letter B one of the numbers could be negative but lower than the positive number so the sum will be positive...does it make sense?

ARE THE INTEGERS Z AND F TO THE RIGHT OF 0 ON THE NUMBER LINE?

1- THE PRODUCT OF Z AND F IS POSITIVE
2- THE SUM OF Z AND F IS POSITIVE

THANKS EVERYONE!
Source: — Data Sufficiency |

User avatar
Legendary Member
Posts: 519
Joined: Sat Jan 27, 2007 7:56 am
Location: India
Thanked: 31 times

Re: GMAT PREP QUESTION

by Neo2000 » Wed Sep 05, 2007 8:09 pm
charmingirl8 wrote:Can anyone help? The answer is C but i don't agree with it as for letter B one of the numbers could be negative but lower than the positive number so the sum will be positive...does it make sense?

ARE THE INTEGERS Z AND F TO THE RIGHT OF 0 ON THE NUMBER LINE?

1- THE PRODUCT OF Z AND F IS POSITIVE
2- THE SUM OF Z AND F IS POSITIVE

THANKS EVERYONE!
From 1 they could either be both positive or both negative.
From 2 both could be positive or one of the numbers could be negative but lower than the positive number so the sum will be positive so cannot be said.

Therefore combining both
Both have to be positive.

Hence C

Junior | Next Rank: 30 Posts
Posts: 22
Joined: Fri May 04, 2007 3:51 am

by krishnamurthyu » Thu Sep 06, 2007 11:15 pm
Given :
Q- Y-N;
is Z,F < 0;

1. Z * F = +Ve ==
(Z,F) = ( +v,+v) : No
(Z,F) = (-v , -v ) : Yes
Insufficient:

2.Z+F = +v
Z,F = (+v,+v) : No
Z > F ( +v,-v ) : F <0, Z<0 :
Insufficient:

1+2:
from 1 ; It (Z,F) has to (-ve,-ve) or (+v,v)
from 2 : (Z,F) (+v,+v)
Hence : (Z,F) = (+v,+v) : Z,F >0 : No

C: Sufficientg